Interpretation of standards and guidelines for the interpretation of sequence variants: a joint consensus recommendation of the American College of Medical Genetics and Genomics and the Association for Molecular Pathology / 中华实验眼科杂志

Sequencing technology has evolved rapidly with the advent of high-throughput next-generation sequencing (NGS). By adopting NGS, more and more ophthalmologists and medical institutions are now performing genetic testing for molecular diagnosis and genetic research in genetic ocular disorders.Genetic testing has gradually become an indispensable test item in the diagnosis and treatment of patients with monogenetic ocular diseases and has been accompanied by new challenges in sequence interpretation due to increased complexity.As we know, NGS can detect a large number of the genetic variation data.Without strict standards to distinguish pathogenic variation from many potential functional variations in the human genome, false positive judgments of causality may be accelerated, which may hind the application and promotion of genetic diagnosis in clinical diagnosis as well as the biological understanding of diseases.The American College of Medical Genetics and Genomics (ACMG) has developed guidances for the interpretation of sequence variants and the Chinese Branch of Genetic Counseling has organized some experts in the field of genetic compiled the Chinese version of the ACMG Standards and Guidelines, which is one of the reference bases to help us interpret genetic variation.This article interpreted the ACMG Standards and Guidelines in order to provide reference for Chinese ophthalmologists in the classification of genetic variation, determination of pathogenic variation, application in clinical diagnosis and related genetic research.

Genotypes and phenotypes of hereditary eye diseases associated with early-onset high myopia / 中华实验眼科杂志

Objective:To analyze the genotype of hereditary eye diseases with early-onset high myopia (eoHM) and its relationship with phenotype.Methods:The families with eoHM were collected in Ningxia Eye Hospital from January 2019 to June 2020.The medical records of the probands and their family members were inquired and recorded in detail, and the relevant ocular examinations were performed.Peripheral venous blood samples were collected from patients and their family members, and whole-genome DNA was extracted.Sequence capture sequencing technology was applied to screen for disease-causing gene mutations in probands.The detected suspected pathogenic variants were verified by Sanger sequencing and were analyzed by family cosegregation analysis.According to ACMG guidelines, the pathogenicity of novel variants was evaluated.The original literature about hereditary eye diseases with eoHM was searched to analyze the relationship between mutated genes and clinical phenotype.This study protocol adhered to the Declaration of Helsinki.All subjects or their guardians were informed of the purpose and procedure of the study and signed the informed consent form.The study protocol was approved by the Ethics Committee of the People's Hospital of Ningxia Hui Autonomous Region (No.2016018).Results:A total of 20 eoHM families were collected, among which pathogenic variants associated with inherited eye diseases were detected in 8 families.Of the 8 probands, two were diagnosed with familial exudative vitreoretinopathy, one with X-linked retinitis pigmentosa, one with congenital stationary nightblindness, one with Stickler syndrome, one with achromatopsia, one with Leber congenital amaurosis, and one with gyrate atrophy of the choroid and retina.The first diagnosis age of the 8 probands was 4-7 years old, and they were all diagnosed as high myopia, with a refractive status ≤-6.00 DS.Genetic tests showed that the 8 probands carried a heterozygous variant c. 313A>G (p.M105Val) in FZD4 gene, a heterozygous variant c. 14_15insAAGA (p.Asp5fs *) in TSPAN12 gene, a heterozygous frameshift variant c. 2234_2237del (p.Arg745fs) in RPGR gene, a compound heterozygous variant of c. 481C>T (p.Gln161Ter *) and c. 355>T (p.Arg119Cys *) in GPR179 gene, a frameshift variant c. 1659_1660insACGGTGACCCTGGCCGTCCTGG (p.Pro554fs *) in COL2A1 gene, a compound heterozygous variant of c. 1811C>T (p.Thr604Ile *) and c. 967G>A (p.Gly323Ser) in PDE6B gene, a compound heterozygous variant of c. 604_619delTCCACGGCACTCAGGG (p.Ser202fs *) and c. 995G>C (p.Arg332Pro) in GUCY2D gene, a homozygous variant c. 772C>T (p.Pro241Leu) in OAT gene.Seven of them were novel variants.Compared with the previous literature, the clinical and gene phenotypes of the 8 families were analyzed in detail in this study, which provided the basis for the diagnosis of hereditary eye diseases with eoHM. Conclusions:EoHM is closely related to some hereditary eye diseases, which may be the reason for the early diagnosis of children and an important clue for clinicians to detect potential hereditary eye diseases.Further clinical evaluations of ocular structure and function as well as genetic screening in children with eoHM are recommended.

Progress in the research on clinical features of Bestrophinopathies and mutations in BEST1 gene / 中华实验眼科杂志

Bestrophinopathies are a group of inherited macular dystrophies caused by BEST1 gene mutations including Best vitelliform macular dystrophy, adult-onset vitelliform macular dystrophy, autosomal dominant vitreoretinochoroidopathy and autosomal recessive bestrophinopathy.The main pathological mechanism of bestrophinopathies is that the primary lesion located in the retinal pigment epithelium will affect the photoreceptor cells.The mutations in BEST1 gene not only result in macular lesions, but also potentially affect the development of eyeball, and even cause serious complications such as angle-closure glaucoma and choroidal neovascularization.It is highly heritable and clinically heterogeneous.The same pathogenic mutation site in BEST1 can lead to different clinical phenotypes, which are complex and varied and can bring great confusion to clinicians, causing misdiagnosis and missed diagnosis the disease.This review aimed to summarize and analyze the clinical manifestations of bestrophinopathies and the research progress in BEST1 gene mutations, so as to improve the understanding of clinicians toward this kind of disease and provide reference for clinical practice and future research.

Genotypes and clinical phenotypes of Hermansky-Pudlak syndrome / 中华实验眼科杂志

Objective:To analyze the genotypes and clinical phenotypes of two families with Hermansky-Pudlak syndrome (HPS).Methods:The method of pedigree investigation was adopted.A Han Chinese HPS family and a Hui Chinese HPS family were enrolled in People's Hospital of Ningxia Hui Autonomous Region from June 2020 to May 2021.Clinical data of two probands and their phenotypically normal parents were collected.Relevant ocular and systemic examinations were carried out.Platelet dense granules in the two probands were observed with an electron microscope.DNA was extracted from peripheral venous blood collected from the subjects.The pathogenic genes were screened by whole exome sequencing.The potential disease-causing variations were analyzed by bioinformatics analysis.Validation and family cosegregation analysis of the pathogenic variations were performed by Sanger sequencing.The relationship between HPS-related gene variations and clinical characteristics was explored.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Ningxia Eye Hospital, People's Hospital of Ningxia Hui Autonomous Region (No.2016018).Written informed consent was obtained from each subject or custodian before any medical examination.Results:The two families were consistent with autosomal recessive inheritance pattern.In family 1 with a family history of consanguineous marriage, the proband had no obvious hypopigmentation on his facial skin, hair, eyebrows and eyelashes.Horizontal nystagmus, exotropia, mild visual impairment, iris atrophy, positive light transmission, orange fundus, pigment loss, macular hypoplasia, prolonged prothrombin time in laboratory examination, and a significant reduction of platelet dense granules by electron microscopy were observed.The proband in family 2 had pale brown hair and eyebrows, severe visual impairment, normal iris pigment, longer thrombin time in laboratory tests, and characteristics similar to those of the proband in family 1.A novel homozygous variant c. 2887G>T (p.E963X) was detected in the HPS3 gene of the proband in family 1.The parents of the proband from family 1 both carried a heterozygous variant c.2887G>T (p.E963X).Compound heterozygous variants were detected in HPS5 gene of the proband in family 2, c.2952-2A>C splicing variation and heterozygous deletion (a 3 144-bp deletion, located in chr11: 18302108-18305251, exon 22).The parents of the proband from family 2 carried a heterozygous variation.The three novel variations were labeled as pathogenic according to the ACMG standards and guidelines. Conclusions:Family 1 is with HPS-3 and family 2 is with HPS-5.There is a certain genotype-phenotype correspondence in the two types of HPS.

Attaching importance to the genetic diagnosis of early-onset high myopia / 中华实验眼科杂志

According to the onset age, high myopia can be divided into late-onset high myopia (loHM) and early-onset high myopia (eoHM). Numerous genetic studies have shown that eoHM is different from loHM.EoHM, a special type of high myopia before school age (<7 years old), is more likely influenced by genetic factors with less contribution from environment.Therefore, individuals with eoHM are an available group for the research of pathogenesis of high myopia as a monogenic disease, and eoHM should be a unique resource in searching for genes responsible for high myopia.EoHM can be divided into nonsyndromic type which only presents with simple high myopia without any ocular or systemic abnormalities, and syndromic type that has other ocular or systemic disorders.More often, eoHM is the earliest sign of some inherited ocular diseases and the first reason for children seeking medical attention, which is an important clue for clinicians to detect underlying eye diseases.Therefore, in addition to further specific clinical examination of ocular structure and function, high attention should be paid to genetic screening of eoHM in order to promote early diagnosis and effective intervention, and long-term follow-up assessment.

Phenotypic analysis of patients with Leber congenital amaurosis caused by new gene mutations / 中华眼底病杂志

Objective:To identify 3 the disease-causing genes and mutations of Leber congenital amaurosis (LCA), and to study the correlation of phenotype and genotype.Methods:A retrospective study. Four LCA patients and seven family members who were diagnosed by eye examination in Ning Xia Eye Hospital of People's Hospital of Ningxia Hui Autonomous Region from January to December 2021 were included in the study. Four patients were from 3 unrelated families. Detailed collection of medical history and family history were received. Related ophthalmologic examination were collected and genomic DNA was extracted from peripheral blood. Whole-exome sequencing method was used for genetic diagnosis. The identified variant was confirmed with Sanger sequencing. Potential pathogenic mutation was analyzed using software and conserved domain analysis and performed co-separated analysis between the family member and the proband.Results:Of the 4 patients, 1 patient was males and 3 patients were females; the age was from 4 to 18 years. Nystagmus were seen in 3 cases, finger pressing eyes and night blindness was seen in 1 cases; electroretinogram showed 4 cases of extinction or near extinction. The foveal reflection was visible in all eyes, and there was no obvious abnormality in the peripheral retina. One eye had strong reflection signal with raised ellipsoid in macular area; two eyes had weak reflection signal faintly visible between retinal layers; 1 eye had increased blood vessel branches, peripheral retinal non-perfusion area with capillary leakage; annular strong autofluorescence in macular area 4 eyes. No obvious abnormality was found in the phenotypes of family members. Genetic testing showed that the proband of pedigree 1 (Ⅱ-1) was found a homozygous missense mutation in c.640A>T (p.C214S) (M1) of PRPH2 gene. The proband of pedigree 2 (Ⅱ-2) was found compound heterozygous mutation in c.1256G>A(p.R419Q) (M2) and c.1A>C (p.M1L) (M3) of TULP1 gene. The proband 3 (Ⅱ-1) and her sister (Ⅱ-2) were both found compound heterozygous mutation in c.1943T>C (p.L648P) (M4) and c.380C>T (p.P127L) (M5) of GUCY2D gene. The parents and sister (Ⅱ-1) of the proband in family 2 and the parents of the proband in family 3 were all carriers of the corresponding heterozygous variant. M1, M3, M4, M5 were novel mutations and unreported. The genotype and disease phenotype were co-segregated within the family. According to the analysis of pedigree and genetic testing results, all 3 families were autosomal recessive inheritance. The amino acid conservation analysis found that M1, M2, M3, M4, and M5 were highly conserved among species. The results of bioinformatics analysis were all pathogenic variants. Conclusions:PRPH2 gene M1, TULP1 gene M3, and GUCY2D gene M4, M5 were novel mutations and not been reported in the literature and database. This research expanded the gene mutation spectrum of LCA. The patients with LCA have available characterristics, including onset age, varying ocular fundus and severe visual impairment.

Cone-rod dystrophy associated with novel variations on CDHR1 and C2orf71 gene / 中华眼底病杂志

Objective:To observe and analyze the gene mutation and clinical phenotype of patients with cone and rod dystrophy (CORD).Methods:A pedigree investigarion. Two CORD pedigrees including 2 patients and 6 family members were enrolled in Ningxia Eye Hospital of People' Hospital of Ningxia Hui Automous Region for this study. The patients were from 2 unrelated families, all of whom were probands. Take medical history with best-corrected visual acuity (BCVA), color vision, slit lamp microscopy, indirect ophthalmoscopy, fundus color photography, optical coherence tomography (OCT), autofluorescence (AF), fluorescein fundus angiography (FFA), electroretinogram (ERG). The peripheral venous blood of patients and their parents was collected, whole genome DNA was extracted, Trio whole genome exome sequencing was performed, Sanger verification and pedigree co-segregation were performed for suspected pathogenic mutation sites. According to the law of inheritance, family history was analyzed to establish its genetic type. Mutational loci pathogenicity was analyzed according to the American College of Medical Genetics (ACMG) guidelines and 4 online tools.Results:Two CORD families showed autosomal recessive inheritance. The proband of pedigree 1 was female, 49 years old. Binocular vision loss with photophobia lasted for 9 years and night blindness for 4 years. The BCVA of right eye and left eye were 0.03 and 0.06, respectively. The results of ERG showed that the amplitudes of dark adaptation 0.01 b-wave and dark adaptation 3.0 a-wave and b-wave in both eyes were slightly decreased, and the amplitudes of light adaptation 3.0 a-wave and b-wave were severely decreased. The proband of pedigree 2 was male, 30 years old. Vision loss in both eyes for 4 years. Denying a history of night blindness. The BCVA of right eye and left eye were 0.3 and 0.2, respectively. The results of ERG showed that the amplitudes of dark adaptation 0.01 b-wave and dark adaptation 3.0 a-wave and b-wave in both eyes were slightly decreased, and the amplitudes of light adaptation 3.0 a-wave and b-wave were severely decreased. The color of optic disc in both eyes was light red, the macular area was atrophic, the foveal reflection disappeared, and the peripheral retina was punctate pigmentation. The main fundus changes in 2 patients were macular atrophy. The proband of pedigree 1 carried compound heterozygous variations c.439-2A>G (M1) and c.676delT (p.F226fs) (M2) on CDHR1 gene. Her father and mother carried M2 and M1 heterozygous mutations, respectively. The proband of pedigree 2 carried compound heterozygous variations c.2665dupC (p.L889fs) (M3) and c.878T>C (p.L293P) (M4) on C2orf71 gene. His father and mother carried M4 and M3 heterozygous mutations, respectively. According to ACMG guidelines and on line tools, 4 variations were considered as pathogenic level. Conclusions:M1 and M2 of CDHR1 gene and M3 and M4 of C2orf71 gene are new pathogenic mutations of CORD. All patients presented with the clinical phenotype of decreased visual acuity and macular atrophy.

Genotype and clinical phenotype analysis of a five-generation Ningxia family with autosomal dominant retinitis pigmentosa pedigree / 中华实验眼科杂志

Objective:To identify the pathogenic mutation in a five-generation Ningxia family with autosomal dominant retinitis pigmentsoa (adRP) and to analyze its associated clinical phenotype.Methods:One adRP pedigree was recruited for this study.All the patients and family members received complete ophthalmic examinations.DNA was abstracted from peripheral blood of three patients, one normal family member and 300 normal controls.Using whole exome sequencing (WES) chip and bioinformatics analysis to screen the candidate disease-causing mutations.PCR and direct sequencing were used to confirm the disease-causing mutations.Genotype-phenotype correlation was also analyzed.This study followed the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of People's Hospital of Ningxia Hui Autonomous Region (No.20160204).Results:PRPF31 c. C1048T (p.Q350X) nonsense mutation was identified as the disease-causing mutation for this family by WES chip, PCR and direct sequencing.This family demonstrated early onset of the disease by presenting nyctalopia from 5 to 6 years, performed rapid disease progression, severely impaired visual function and posterior subcapsular cataract.The fundus presentations and electroretinogram (ERG) results showed typical RP progressions. Conclusions:PRPF31 c. C1048T (p.Q350X) nonsense mutation is the disease-causing mutation of this family.This mutation is first reported in Chinese with distinct phenotypes in the present family, including early onset of the disease, rapid disease progression, severely impaired visual function and posterior subcapsular cataract.

Analysis of genotype and phenotype of hereditary retinal diseases which are easily misdiagnosed as amblyopia / 中华实验眼科杂志

Objective@#To analysis the genotype and phenotype of hereditary retinal diseases (HRD) which are easily misdiagnosed as amblyopia.@*Methods@#A case-control study was designed.The patients with HRD who were misdiagnosed as amblyopia in Ningxia Eye Hospital from January to December, 2017 were recruited in this study.The clinical medical history and ophthalmic examinations of patients and their family members were recorded, and family maps were drawed.Peripheral venous blood (5 ml) from each patient and their family members was collected, and genomic DNA was extract.The target sequence capture sequencing technology was used to detect the genetic testing in serum of the patient, and the pathogenic mutation site was determined by Sanger sequencing and co-segregation verification.Genetic testing results with related ophthalmic examination were considered together to analyze the relationship between genotype and phenotype.This study followed the Declaration of Helsinki.Written informed consent was obtained from each subject or the guardian prior to entering study cohort.This study protocol was approved by Ethic Committee of People's Hospital of Ningxia Hui Autonomous Region Hospital (No.2016018).@*Results@#Twenty-two patients with HRD were enrolled in the study, including 10 Stargardt disease (STGD), 8 cases of cone dystrophy (COD) or cone and rod dystrophy (CRD), and 5 cases of familial exudative vitreoretinopathy(FEVER). Nine patients were detected to have pathogenic mutations, and the positive rate was 40.9%, of which 4 patients with STGD carried mutation gene, including ABCA4 and PROM1 genes; mutations in RPGR, PROM1 and GUCY2D genes were detected in 3 patients with COD or CRD; TSPAN12 gene mutation were detected in 2 patients with FEVER.Eleven mutation sites were detected, 4 of which were newly discovered mutation sites.All of the patients in 9 HRD families developed symptoms during adolescence.At the early stage of the disease, there was severe damage to the eyesight, but the fundus was normal or only slightly abnormal.As the disease progressed, the fundus changes were characteristic, and there were clinical phenotypic overlap between some diseases.All family genotypes and clinical phenotypes were co-separated.@*Conclusions@#The main pathogenic gene of STGD is ABCA4 gene, and PROM1 gene can also cause partial STGD; COD and CRD have similar clinical manifestations, and the pathogenic genes also cross each other, and the genetic pattern is diverse; FEVER caused by mutation of TSPAN12 gene is autosomal dominant, and the mutation type has missense mutation and frameshift mutation.HRDs lack typical early clinical signs, and genetic diagnosis can provide pre-symptomatic diagnosis.

Evaluation of thyroid-associated ophthalmopathy activity by using magnetic resonance fat quantification technology / 中华实验眼科杂志

Objective@#To explore the value of magnetic resonance fat quantification technology (MR mDixon-quant) in evaluating thyroid-associated ophthalmopathy (TAO) activity.@*Methods@#Case control study was performed.Fifty patients (100 eyes) with TAO which met Mourits criterion were enrolled from September 2016 to March 2018 in Ningxia Hui Autonomous Region People's Hospital.The TAO patients were grouped by clinical activity score (CAS). Twenty nine patients (58 eyes) with CAS≥3 served as TAO active group, twenty one patients (42 eyes) with CAS<3 served as TAO non-active group.Twenty three healthy subjects (46 eyes) were collected as normal control group at the same time.All subjects underwent orbital MR mDixon-quant and MR imaging.Orbital fat content (FF values) and exophthalmus was calculated on MR work-station.FF values and degree of exophthalmus were analyzed by analysis of variance.The correlation of FF values and CAS in TAO patients was conducted by Spearman rank correlation analysis.The cut-off values of FF in predicting TAO activity was determined by receiver operating characteristics (ROC) curve.The Kappa consistency test was chosen to assess the consistency of CAS and FF values.Intraclass correlation coefficient (ICC) were used to analyze the intra-observer and inter-observer repeatability of the FF values and the degree of exophthalmus.This study was approved by the Ethics Committee of Ningxia Hui Autonomous Region People's Hospital (No.20160718). All the candidates signed informed consent.@*Results@#The FF values were (85.190±4.346)%, (88.715±5.686)% and (82.345±5.445)% in TAO active group, TAO inactive group and normal control group, respectively, with a significant difference among the 3 groups (F=17.072, P<0.001). The FF values of TAO active group and TAO inactive group were significantly higher than that of control group, and the FF value of TAO active group was significantly lower than that of TAO inactive group (all at P<0.01). The degrees of exophthalmos were (20.221±1.714), (20.855±2.103) and (15.363±1.667)mm in TAO active group, TAO inactive group and normal control group, respectively, with a significant difference among the three groups (F=126.298, P<0.01). The degrees of exophthalmos in TAO active group and TAO inactive group were significantly higher than that in normal control group (both at P<0.01), there was no statistical difference in degrees of exophthalmos between TAO active group and TAO inactive group (P<0.05). Spearman rank correlation revealed that FF value was negative correlated with CAS (rs=-0.443, P<0.01). The cut-off value of FF value was 87.180%, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 74.14%(43/58), 66.67%(28/42), 75.44%(43/57), 65.12%(28/43) and 71.00%(71/100), respectively.There were consistencies of FF values with the CAS (Kappa=0.431, P<0.001). The intra-observe and inter-observer reproducibility were fairly good for FF value (ICC=0.953, 0.920) and degree of exophthalmus (ICC=0.935, 0.917).@*Conclusions@#MR mDixon-quant can quantitative measure orbital fat with good measurement repeatability.Fat quantification technology by MR is valuable in evaluating TAO activity.

Gene mutation spectrum analysis of retinitis pigmentosa patients in Ningxia Region of China / 中华实验眼科杂志

Objective@#To analysis the gene mutation spectrum of retinitis pigmentosa (RP) patients in Ningxia Region of China.@*Methods@#Fifty-five pedigrees and 74 sporadic RP patients were included in Ningxia Eye Hospital from January 2015 to December 2016.Two hundred unrelated healthy adults were enrolled as normal controls during the same period.The clinical features of patients and their family members were evaluated by ophthalmic examinations, including visual acuity, best corrected visual acuity, fundus examination, optical coherence tomography, fundus fluorescein angiography, and visual field and electroretinogram.The next generation sequencing, PCR and direct sequencing were used to confirm the pathogenic mutation.This study was approved by Ethic Committee of the Ningxia Eye Hospital (NO.20150107), and informed consent was obtained from each subject.@*Results@#The mutations were detected in 37 RP pedigrees, 8 pedigrees showed autosomal dominant inheritance and 6 pathogenic genes were confirmed, all the autosomal dominant RP (ADRP) patients carried a single heterozygous mutation.Twenty-five pedigrees were autosomal recessive RP (ARRP) and 12 pathogenic genes were confirmed.Among ARRP patients, the mutations rate of USH2A gene was the highest, accounting for 28% (7/25), EYS gene and MYO7A gene accounted for 12% (3/25). Four X-linked RP (XLRP) pedigrees carried the homozygous mutations on RPGR gene.Twenty-five disease-causing genes were detected in 49 sporadic RP patients.The mutation rate of USH2A gene was the highest, accounting for 26.5% (13/49), followed by RP1 gene, accounting for 8.1% (4/49).@*Conclusions@#Recessive inheritance is the most common cause of RP.USH2A gene is the main pathogenic gene of RP in Ningxia region of China.

Gene mutation spectrum analysis of retinitis pigmentosa patients in Ningxia Region of China / 中华实验眼科杂志

Objective To analysis the gene mutation spectrum of retinitis pigmentosa ( RP ) patients in Ningxia Region of China. Methods Fifty-five pedigrees and 74 sporadic RP patients were included in Ningxia Eye Hospital from January 2015 to December 2016. Two hundred unrelated healthy adults were enrolled as normal controls during the same period. The clinical features of patients and their family members were evaluated by ophthalmic examinations,including visual acuity,best corrected visual acuity,fundus examination,optical coherence tomography, fundus fluorescein angiography,and visual field and electroretinogram. The next generation sequencing,PCR and direct sequencing were used to confirm the pathogenic mutation. This study was approved by Ethic Committee of the Ningxia Eye Hospital (NO. 20150107),and informed consent was obtained from each subject. Results The mutations were detected in 37 RP pedigrees, 8 pedigrees showed autosomal dominant inheritance and 6 pathogenic genes were confirmed,all the autosomal dominant RP ( ADRP ) patients carried a single heterozygous mutation. Twenty-five pedigrees were autosomal recessive RP ( ARRP) and 12 pathogenic genes were confirmed. Among ARRP patients,the mutations rate of USH2A gene was the highest,accounting for 28％ (7/25),EYS gene and MYO7A gene accounted for 12％ (3/25). Four X-linked RP (XLRP) pedigrees carried the homozygous mutations on RPGR gene. Twenty-five disease-causing genes were detected in 49 sporadic RP patients. The mutation rate of USH2A gene was the highest, accounting for 26. 5％ ( 13/49 ) , followed by RP1 gene, accounting for 8. 1％ ( 4/49 ) . Conclusions Recessive inheritance is the most common cause of RP. USH2A gene is the main pathogenic gene of RP in Ningxia region of China.

Analysis of the genotype and phenotye in 3 pedigrees with Stargardt disease / 中华实验眼科杂志

Objective To analyze the relationship between genotype and phenotype in 3 pedigrees with Stargardt disease.Methods Three pedigrees with Stargardt disease were included in Ningxia Eye Hospital from January 2017 to September 2017.The clinical features of patients and other family members were evaluated by ophthalmic examinations,including visual acuity,best corrected visual acuity (BCVA),fundus examination,optical coherence tomography (OCT),fundus fluorescein angiography (FFA) and electroretinogram (ERG).The periphery blood sample of 5 ml from patients and 1 family member with normal phonotye in each family were collected.The next generation sequencing,PCR and direct sequencing were used to confirm the disease-causing mutation.The relationship between genotype and phenotype was analyzed.This study was approved by Ethic Committee of Ningxia Eye Hospital and informed consent was obtained from each subject.Results In 3 Stargardt pedigrees,2 pedigrees showed autosomal recessive inheritance,and 1 pedigree was pseudodominant inheritance.Five mutations on ABCA4 gene were detected and p.F2188S and p.Y345C were novel muations.All pedigrees carried two heterozygous mutation.The onset age of the patients were adolescence except just one patient who suffered at the age of 50 years old.The visual acuity was severely affected and the OCT indicated different degrees of macular atrophy.The results of the ocular fundus photography and the FFA were variable.Conclusions The patients with stargardt disease often carry heterozygous mutation on ABCA4 gene and available characteristics,including early onset age,varying ocular fundus and severe visual impairment.Next generation sequencing technique shows the advantages of rapid and high efficiency in the diagnosis of Stargardt disease.

Genotype and clinical phenotype analysis in patients with retinitis pigmentosa and cone rod dystrophy / 中华眼底病杂志

Objective To observe the gene mutation and clinical phenotype of patients with retinitis pigmentosa (RP) and cone rod dystrophy (CORD).Methods Thirty-seven patients with RP and 6 patients with CORD and 95 family members were enrolled in the study.The patient's medical history and family history were collected.All the patients and family members received complete ophthalmic examinations to determine the phenotype,including best corrected visual acuity,slit lamp microscope,indirect ophthalmoscopy,color fundus photography,optical coherence tomography,full-field electroretinogram,and fluorescein fundus angiography.DNA was abstracted from patients and family members.Using target region capture sequencing combined with next-generation sequencing to screen the 232 candidate pathogenic mutations.Polymerase chain reaction and direct sequencing were used to confirm the pathogenic pathogenic mutations and Co-segregation is performed among members in the family to determine pathogenic mutation sites.The relationship between genotype and clinical phenotype of RP and CORD was analyzed.Results Of the 37 patients with RP,13 were from 6 families,including 4 families with autosomal dominant inheritance,2 families with autosomal recessive inheritance,and 3 in 6 families were detected pathogenic gene mutations.24 cases were scattered RP.Six patients with CORD were from four families,all of which were autosomal recessive.Of the 43 patients,21 patients were detected the pathogenic gene mutation,and the positive rate was 48.8％.Among them,15 patients with RP were detected 10 pathogenic gene mutations including USH2A,RP1,MYO7A,C8orf37,RPGR,SNRNP200,CRX,PRPF31,C2orf71,IMPDH1,and the clinical phenotype included 10 typical RP,2 cases of RPSP,3 cases of Usher syndrome type 2 and 6 cases of CORD patients were all detected pathogenic gene mutations,including 2 cases of ABCA4,2 mutations of RIMS 1 gene,1 case of CLN3 gene mutation,and 1 case of CRB 1 and RPGR double gene mutation.Conclusions RP and CORD are clinically diverse in genotype and clinically phenotypically similar.For patients with early RP and CORD,clinical phenotype combined with genetic analysis is required to determine the diagnosis of RP and CORD.

Rapid identification of pathogenic mutations in sporadic hereditary retinal dystrophies using targeted next-generation sequencing / 中华实验眼科杂志

Background Hereditary retinal diseases (HRDs) are a group of retinal degenerative diseases with significant genetic and clinical heterogeneities.Traditional techniques are challenging for detection of pathogenic mutations.Objective This study was to identify the diseasing-causal genes in 20 Chinese families with a variety of HRDs.Methods Family histories and ophthalmic examinations were obtained from all participants in 20 sporadic families.Targeted sequence capture array technique with next-generation sequencing (NGS) was performed to detect pathogenic mutations in 232 identified genes associated with HRDs.Variants detected by NGS were filtered by bioinformatic analysis HRDs.Genotype-phenotype correlation was also assessed.Results We identified 11 patients with pathogenic mutations,including 8 compound heterozygous mutations and 3 homozygous mutations,which were not yet reported.These findings showed genetic diagnoses in 11 of 20 patients,with the positive rate of 55％.Among them,6 patients were autosomal recessive inheritance and 5 were unspecific.Identification of different mutations and divergent phenotypes revealed 5 patients were affected with cone-rod dystrophy,3 patients with Leber congenital amaurosis,1 patient with congenital stationary night blindness,1 patient with Best vitelliform macular dystrophy and 1 patient with Stargardt disease.Conclusions Targeted NGS is an effective approach for the genetic diagnoses of HRDs.These findings provide insights into understanding the genotype-phenotype correlations in HRDs.

Associations of single nucleotide polymorphisms of VEGFRI and smoking with age-related macular degeneration in Hui and Han populations from Ningxia region in China / 中华实验眼科杂志

Background Age-related macular degeneration (AMD) is a heritable,progressive degenerative disorder that triggers central visual impairment.Research demonstrated that the single nucleotide polymorphisms (SNPs) of vascular endothelial growth factor 1 (VEGFR1) gene is associated with AMD in different population.However,the results varied among diversified ethnic origin composition and distinct regions.Objective This study was to investigate the associations between the SNPs of VEGFR1 genetic variants along with smoking exposure and the risk of AMD in Hui and Han ethnics in the Ningxia population in China.Methods A case-control study was conducted.Four hundreds and thirty-two AMD patients including 325 Han ethnic patients and 107 Hui ethnic patients were recruited from March 2011 to June 2015,and 906 ethnicity-and gender-matched age-related cataract patients were contemporaneously recruited as control group,including 698 Han ethnic patients and 208 Hui ethnic patients.Periphery blood sample of 5 ml was collected from the subjects and genomic DNA was prepared.Eight tagging SNPs loci were acquired to cover rs2281827,rs3936415,rs7337610,rs7981680,rs9554320,rs9554322,rs9582036 and rs9943922,and the genotypes of SNPs were detected by using MassARRAYTM time-of-flight mass spectrometry system.Chi-square test and multi-factor Logistic regression analysis were utilized to estimate the discrepancy of allele frequency and genotype distribution in Hui and Han AMD patients.Moreover,the correlation of AMD with smoking and age statue were further analyzed.This study protocol complied with Helsinki Declaration and was approved by Ethic Committee of Ningxia Eye Hospital.Written informed consent was obtained before any relevant medical examination.Results There were significant differences in the age between AMD group and control group in both Han and Hui ethnicity (Han:P =0.000;Hui:P =0.009).The smoking exposure was significantly different between AMD group and control group in Han ethnicity (P =0.000),and smoking was the independent risk factor of AMD disease in Han ethnicity of N ingxia region (odds ratio [OR] =2.622,95％ confidence interval [CI]:1.899-3.619).The allele frequencies of SNPs were not significantly different in the AMD patients between Han and Hui ethnicity (all at P＞0.05).However,the allele frequencies and genotype distribution of rs7337610 and rs9554322 SNPs were significantly different between the AMD group and control group in both Han and Hui ethnicity (all at P=0.00).The genotype distribution of rs9582036 and rs9943922 SNPs was significantly different between the AMD group and control group in Han ethnicity (P=0.02,0.00).Allelic G of rs7337610 was the protective factor of AMD disease in Han and Hui ethnieity (OR=0.354,95％ CI:0.288-0.435;OR=0.446,95％ CI:0.315-0.632),while allelic C of rs9554322 was the risk factor of AMD disease in Han and Hui ethnicity (OR=1.671,95％ C1:1.234-2.262;OR=3.661,95％ CI:2.156-6.218).Allelic A of rs9582036 was the risk factor of AMD disease in Han ethnicity (OR =1.477,95％ CI:1.124-1.940).Conclusions Smoking is the independent risk component for Han population with AMD.Of the eight SNPs tagged,the genotypes and alleles of rs9554322 and rs7337610 seems to confer susceptibility to AMD in both Han and Hui ethnicity,the genotypes and alleles of rs9582036 and rs9943922 confer susceptibility to AMD in only Han ethnicity.

Detection of disease-causing gene in a Hui congential cataract pedigree by exon combined target region capture sequencing chip / 中华实验眼科杂志

Background Congenital cataract is an important cause of blindness and amblyopia in children,and about 50％ of congenital cataract is hereditary.Objective The aim of this study was to determine the diseasecausing gene of one Hui congenital cataract pedigree by using exon combined target region capture sequencing chip of eye diseases.Methods This study was approved by Ethic Committee of Ningxia People's Hospital and followed Declaration of Helsinki.One Hui congenital cataract pedigree was recruited in Ningxia Eye Hospital in 2011.All the disease history of the members in this family were collected and recorded,and the eye examinations were performed.The peripheral blood specimens were collected from family members and 300 healthy individuals for the extraction of DNA.Exon combined target region capture sequencing chip of eye diseases was used to screen the candidate diseasecausing mutations,then PCR and direct sequencing were used to confirm the disease-causing mutations.Results This H ui family included 61 members of 6 generations,and 18 patients were diagnosed in serial 5 passages,conforming to autosomal dominant inheritance pattern.Among 18 cataract patients,7 individuals were associated with nystagmus and strabismus,and 4 patients had high myopia.Eight candidate pathogenetic mutations were detected by exon combined target region capture sequencing chip of eye diseases and bioinformatics method,with 5 mutations in noncoding regions and 3 in coding regions.The mutation P24T of CYRGD gene was confirmed as pathogenic mutation of this pedigree by using PCR and direct sequencing methods.These mutations co-segregated with affected members of the family,and the mutations were not found in the unaffected family members and 300 unrelated controls.Conclusions P24T of CYRGD gene mutation is confirmed as pathogenic mutation of this pedigree.Exon combined target region capture sequencing chip provides a new approach to detect disease-causing mutations of congenital cataract with diversity clinical phenotypes.

Inhibition of roscovitine on the activity of Cdk5/p25 and phosphorylation of tau in retina of RCS rats after intravitreal injection / 中华实验眼科杂志

Background Study determined that retinitis pigmentosa has a similar pathogenesis mechanism to Alzheimer disease,and activity of cyclin-dependent kinase 5 (Cdk5) and its activators participates in the degeneration of central nervous system.Roscovitine,an inhibitor of Cdk5,can suppress activity of Cdk5/p25 pathway and therefore inhibit cell apoptosis.However,the influence of roscovitine on retinitis pigmentosa(RP) is unclear.Objective This study was to investigate the expressions of p35,p25 and tau in the retinas of RCS rats.Methods Roscovitine of 4 μl was intravitreally injected in the right eyes of 12 SPF 17-day-old RCS rats,and the fellow eyes were not intervened as the control eyes.The rats were sacrificed on eighth day (postnatal 25 days) and eighteenth day (postnatal 35 days),and whole retinas were isolated to evaluate the relative expressions of Cdk5,p35,p25 and tau phosphorylation by Western blot,and the activity of Cdk5/p25 was analyzed by quantitative colorimetric assay.The results were compared between the right eyes and fellow eyes by paired t test.The use and care of the rats complied with Ethic Statement of Experimental Animal of Ningxia Medical University.Results In the eighth and eighteenth day after injection,the relative expression values (A values) of p35 in rat retinas were 1.186±0.019 and 1.069± 0.019 in the injected eyes,showing significant decreases in comparison with 1.364±0.016 and 1.214±0.008 of the fellow eyes (t =-6.294,-6.477,both at P＜0.05);the relative expression values (A values) of p25 in rat retinas were 0.312±0.009 and 0.269±0.018 in the injected eyes,which was significantly lower than 0.595±0.013 and 0.473±0.011 of the fellow eyes (t=-36.508,-11.879,both at P＜0.05).No significant difference was found in the relative expression of Cdk5 protein between the injected eyes and the fellow eyes in various time points after injection (both at P＞0.05).The activities of Cdk5/p25 were (0.003 83 ±0.000 14) mol/(s · mg) and (0.002 01 ± 0.000 11) mol/(s · mg) in the injected eyes,with significant decreases in comparison with the (0.005 47±0.000 27)mol/(s · mg)and (0.003 35±0.000 15) mol/(s · mg) of the fellow eyes (t=-9.152,P=0.000;t=-9.248,P=0.000),and the tau phosphorylation levels followed the same pattern in the eighth and eighteenth day after injection (t =-9.854,-6.744,both at P＜0.05).Conclusions Intravitreal injection of roscovitine can inhibit the activity of Cdk5/p25 and tau phosphorylation level in retinas of RCS rats to certain extend.

Polymorphisms of complement genes and ARMS2/HTRAI in patients with age-related macular degeneration in Ningxia, China / 中华实验眼科杂志

Background Age-related macular degeneration (AMD) is the main cause of irreversible loss of central vision in old population.The incidence of AMD is increasing year by year,but the mechanism is not clearly understood.Objective This study was to investigate the association between genetic variants and the risk of AMD in Ningxia population.Methods This study was approved by Ethic Committee of Ningxia People's Hospital and complied with the Helsinki Declaration.Written informed consent was obtained from each subject.One hundred and fifty patients with AMD and 145 ethnicity-and gender-matched controls were recruited in Ningxia Eye Hospital from January 2012 to March 2013.All individuals underwent comprehensive eye examinations and genomic DNA was prepared from peripheral blood.The single nucleotide polymorphisms (SNPs) of 8 susceptibility loci in four candidate genes,including complement factor H (CFH),complement factor B (CFB),age-related maculopathy susceptibility 2 (ARMS2) and high temperature required factor A1 (HTRA1),were genotyped with Mass Array and MALDI-TOF technique by Sequenom platform.The distribution of genotype was tested for Hardy-Weinberge equilibrium (HWE).The differences of genotype distribution of allele and haplotype frequencies were compared between patients and controls using chi-squared test and the P value was significant at ＜ 0.006 level after correction of age,and the relationship of genotype distribution with AMD was evaluated by Logistic regression analysis.Measures of linkage disequilibrium (LD) was carried out by Haploview.Results All the genetypes met HWE.Seven SNPs were found to be different in the genotypic distributions and allele frequencies between patients and normal controls (all at P＜ 0.05),however,after Bonferroni correction,the differences of only four SNPs were significant between the patients and controls in the genotype and allele distributions,including the SNPs of rs10737680 and rs1410996 in CFH gene,the SNP of rs10490924 in ARMS2 gene and SNP of rs11200638 in HTRA1 gene.The allele distributions of rs800292 (Pallele =0.006,OR =1.643,95 ％ CI:1.155-2.336) in CFH and rs641153 (Pallele =0.002,OR =0.273,95 ％ CI:0.120-0.620) in CFB were significantly associated with AMD.In addition,five SNPs in CFH gene were consisted of two blocks after analysis by Haploview.In addition,five SNPs in CFH were consisted of two blocks after analysis by Haploview.The first one SNPs (including rs551397 and rs800292) and another one SNPs (including rs12124794,rs10737680) and rs1410996 were in strong linkage disequilibrium (D'=1.00).After 50 000 permutations,the GC and AT haplotypes of the first block and the AAC,TCT and ACT haplotypes in the second block were significantly different between AMD patients and controls (P =0.010,0.010,0.001,0.041 and 0.033,respectively).The allel T of rs641153 was a protective factor of AMD (P=0.002,OR =0.273,95％ CI:0.120-0.620).Conclusions The SNPs rs10737680 and rs1410996 in CFH,rs10490924 of ARMS2 gene and rs11200638 of HTRA1 gene are associated with AMD in Ningxia population.

The hereditary types and clinical characteristics of 137 patients with retinitis pigmentosa in Ningxia / 中华眼底病杂志

ObjectiveTo observe the hereditary types and clinical characteristics of 137 patients with retinitis pigmentosa (RP) in Ningxia.MethodsOne hundred and thirty-seven patients with RP who diagnosed by the examinations of visual acuity, optometry, direct or indirect ophthalmoscope, visual field,optical coherence tomography (OCT) and electroretinogram were enrolled. The hereditary types and clinical characteristics were analyzed according to the family history and the results of ophthalmologic examinations.ResultsOne hundred and thirty-seven patients included 29 autosomal dominant RP (ADRP) patients from 8 families (7.4％), 16 autosomal recessive RP (ARRP) patients from 15 families (13. 9％), 10 X-linked RP (XLRP) from 3 families (2.8％), and 82 simplex RP (SRP) patients (75.9％).There were 15consanguineous marriage families out of 26 families with RP history (57.7 ％). The patients were classified as typical RP (102 patients, 74.5％) and atypical RP (35 patients, 25.5％). All the ADRP and XLRP patients showed typical clinical features of RP. Ten (62.5％) of ARRP patients and 53 (64.6％) of SRP patients had typical features of RP. Six (37.5％) of ARRP patients and 29 (35.4％) of SRP patients had atypical features of RP. Among atypical RP patients, 17 (48. 6％) patients were non-pigmented RP which including 3 patients were misdiagnosed as amblyopia during childhood. The logarithm of minimal angle of resolution (logMAR) best corrected visual acuity (BCVA) of ADRP patients was 1.04±0.51 at the age older than 51 years, while the BCVA of ARRP and XLRP patients were 0. 92+0. 61 and 1. 70±0. 02 respectively at 21 to 30 years of age. One hundred and twenty-three (89. 8%) patients suffered from varying degrees of myopia. OCT showed that the average thickness of macular fovea in ADRP patients was ( 185. 73 + 1. 23) μm at the age older than 51 years, while in ARRP and XLRP patients were (173. 21 ± 0. 98) and (170. 49+1. 15) μm respectively at 21 to 30 years of age. Conclusions ADRP and XLRP are typical RP. All atypical RP are ARRP and SRP. Non-pigmented RP are mainly seen in atypical RP which often misdiagnosed as amblyopia during childhood. The photoreceptors in macula are damaged in the early stage and the decline of visual acuity occurred at 21 to 30 years of age in patients with ARRP and XLRP. The ADRP patients has late slower decline of visual acuity and retain some visual acuity at the age older than 51 years.