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.

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.

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.

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.