Molecular genetics research of a Chinese family carrying triple HLA-A alleles / 中国输血杂志

【Objective】 To determine molecular basis of a rare HLA-A typing results carrying triple A alleles in potential allo-HSCT donor and her family. 【Methods】 HLA-A, -B, -C, -DRB1, -DQB1, -E, -F, -G of 5 members in the family were genotyped at a high-resolution level using next-generation sequencing (NGS). HLA-A of probosita was re-checked using polymerase chain reaction-sequence-based typing (PCR-SBT), and SNP oligonucleotide probes (SNP-array)were scanned with genomic DNA of probosita. 【Results】 There was 162.9Kb duplication in 6p22.1(29, 803, 377-29, 966, 301)of probosita who carried triple A alleles A*02∶01∶01, A*11∶01∶01, A*24∶02∶01. Other two family members were found to carry this haplotype: A*02∶01∶01, A*24∶02∶01, B*54∶01∶01, C*01∶02∶01, DRB1*04∶05∶01, DQB1*04∶01∶01, E*01∶01∶01∶03, F*01∶01∶01, G*01∶01∶01∶01, which as a Mendelian gene was segregated and stably transmitted through two generations. 【Conclusion】 Tiny gene duplication induces one haplotype carries two HLA-A alleles in a potential healthy donor for allo-transplantaion and stably transmits through two generations.Routine HLA typing laboratories should pay more attention to this situation and accurately report.

Methods and Research Hotspots of Forensic Kinship Testing / 法医学杂志

Kinship testing is widely needed in forensic science practice. This paper reviews the definitions of common concepts, and summarizes the basic principles, advantages and disadvantages, and application scope of kinship analysis methods, including identity by state (IBS) method, likelihood ratio (LR) method, method of moment (MoM), and identity by descent (IBD) segment method. This paper also discusses the research hotspots of challenging kinship testing, complex kinship testing, forensic genetic genealogy analysis, and non-human biological samples.

Genotype-environment interaction on arterial stiffness: A pedigree-based study / 北京大学学报(医学版)

OBJECTIVE@#To utilized the baseline data of the Beijing Fangshan Family Cohort Study, and to estimate whether the association between a healthy lifestyle and arterial stiffness might be modified by genetic effects.@*METHODS@#Probands and their relatives from 9 rural areas in Fangshan district, Beijing were included in this study. We developed a healthy lifestyle score based on five lifestyle behaviors: smoking, alcohol consumption, body mass index (BMI), dietary pattern, and physical activity. The measurements of arterial stiffness were brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI). A variance component model was used to determine the heritability of arterial stiffness. Genotype-environment interaction effects were performed by the maximum likelihood methods. Subsequently, 45 candidate single nucleotide polymorphisms (SNPs) located in the glycolipid metabolism pathway were selected, and generalized estimated equations were used to assess the gene-environment interaction effects between particular genetic loci and healthy lifestyles.@*RESULTS@#A total of 6 302 study subjects across 3 225 pedigrees were enrolled in this study, with a mean age of 56.9 years and 45.1% male. Heritability of baPWV and ABI was 0.360 (95%CI: 0.302-0.418) and 0.243 (95%CI: 0.175-0.311), respectively. Significant genotype-healthy diet interaction on baPWV and genotype-BMI interaction on ABI were observed. Following the findings of genotype-environment interaction analysis, we further identified two SNPs located in ADAMTS9-AS2 and CDH13 might modify the association between healthy dietary pattern and arterial stiffness, indicating that adherence to a healthy dietary pattern might attenuate the genetic risk on arterial stiffness. Three SNPs in CDKAL1, ATP8B2 and SLC30A8 were shown to interact with BMI, implying that maintaining BMI within a healthy range might decrease the genetic risk of arterial stiffness.@*CONCLUSION@#The current study discovered that genotype-healthy dietary pattern and genotype-BMI interactions might affect the risk of arterial stiffness. Furthermore, we identified five genetic loci that might modify the relationship between healthy dietary pattern and BMI with arterial stiffness. Our findings suggested that a healthy lifestyle may reduce the genetic risk of arterial stiffness. This study has laid the groundwork for future research exploring mechanisms of arterial stiffness.

Clinical and molecular genetic study of a Chinese Han family with X-linked retinoschisis / 中华实验眼科杂志

Objective:To study the clinical phenotype and molecular genetic characteristics of a Chinese Han family with X-linked retinoschisis (XLRS), and to determine the associated gene variations.Methods:A pedigree investigation was performed.The clinical characteristics and pedigree analysis of a Han Chinese family line with XLRS was conducted in August 2021 at the Xiamen Eye Center Affiliated to Xiamen University.All patients and the carriers underwent comprehensive medical history collection and routine ophthalmological examinations, including visual acuity, non-contact tonometer, slit lamp microscope, direct ophthalmoscope, and optical coherence tomography.The proband and some patients underwent medical optometry, fundus photography or wide-angle fundus photography, and electroretinogram examination.Peripheral venous blood samples were collected from the family members, and whole exome sequencing (WES) analysis was performed on the proband samples.For variants screened by WES, the expanded verification in other patients and normal persons in the family was carried out by Sanger sequencing.Multiple bioinformatic tools were used to analyze the pathogenicity of variants.This study protocol was approved by the Ethics Committee of Xiamen Eye Center of Xiamen University (No.XMYKZX-KY-2021-012). Written informed consent forms were obtained from each subject or guardian of minors.CADD, FATHMM and other bioinformatics tools were used to analyze the pathogenicity of the variation sites.Results:The Han XLRS pedigree consisted of 8 individuals in 3 generations.Out of the 3 cases diagnosed with XLRS based on clinical evaluation, all were male.The mother of the proband was a carrier of related genes.There were 5 persons with normal phenotypes.There was no history of consanguineous marriages within the family, and the disease was shown to be intergenerational, which is consistent with the recessive inheritance of the X chromosome.None of the patients had a history of systemic disease or any other abnormal manifestations.The prevailing feature of ophthalmopathy was poor binocular vision since childhood.The proband and his younger brother had spoke split in the macula, and their grandfather showed atrophy of retinal nerve fibers.Genetic analysis revealed a hemizygous variation c. 214G>C: p.Glu72Gln in the RS1 gene in all the patients in this family.The proband's mother was heterozygous at this site, and all other phenotypically normal family members exhibited wild type at this site.This variant was predicted to be a deleterious variation and likely to cause disease based on bioinformatics analysis. Conclusions:The proband and patients in this Han Chinese family have the known c. 214G>C: p.Glu72Gln hemizygous variation of the RS1 gene and exhibit mild XLRS, which was consistent with the recessive inheritance of X chromosome.

Frequency of JK (a-b-) in Yichang: genetic pedigree analysis of Jk (a-b-) and Jka weak expression / 中国输血杂志

【Objective】 To explore the molecular hereditary and frequency of Jk(a-b-) in blood donors in Yichang. 【Methods】 A total of 49 999 samples from Yichang Red Cross Central Blood Station were screened for Jk(a-b-) by urea hemolysis test(2 mol /L). The phenotypes of JK (a-b -) probands and their families were confirmed by monoclonal anti-Jka and anti-Jkb, and the whole exon of SLC14A1 gene was sequenced. 【Results】 The frequency of Jk(a-b-) in Yichang blood donors was 0.004% (2/49 999), and the exon sequencing of SLC14A1 gene confirmed that both two probands were JK*02N.01 caused by c. 342-1G>A homozygous mutation.Besides, JK*01W.01 allele was observed in the pedigree analysis, and weak expression of Jka was found in 4 out of 11 family members. 【Conclusion】 The frequency of JK (a-b -) in Yichang blood donors is similar to those in Shanghai 0.004%(2/48 400), and both caused by JK * 02N.01 allele with high frequency in Southeast Asia. The epidemiological survey of JK * 01w.01 allele frequency should be further performed.

Molecular genetic analysis and predigree of a new FUT1 allele of para-Bombay blood group: a case report / 中国输血杂志

【Objective】 To study the serological and molecular mechanism of a case of para-Bombay blood group caused by 236delG mutation of FUT1 gene and investigate the pedigree. 【Methods】 The ABO, H and Lewis antigens of the proband and her family members were detected serologically, and the ABO blood group was confirmed by gene testing. The FUT1 gene was amplified by PCR and then sequenced. The structure of FUT1 236delG enzyme of the proband was simulated in 3D by SwissModel online server. 【Results】 Serological results showed that the proband was rare para-Bombay ABhm, Le(a-b-). Her father and mother was type A and type B, respectively. The gene results showed that the proband was type AB, while her father and mother was type A and type B, respectively. The sequencing results showed that the proband had 236delG/551_552delAG gene mutation, while her mother had 236delG FUT1 gene mutation, and her father had 551_552delAG FUT1 gene mutation. The 3D simulation of the enzyme structure of the proband FUT1 236delG showed that the translated product was an alpha helix structure with no actual function. 【Conclusion】 The 236delG mutation is a new discovered mutation in FUT1 genotype, with 551_ 552delAG mutation(FUT1* 01N.06 genotype), which can result in the generation of para-Bombay blood group.

Identification and pedigree investigation of B(A) and cisAB blood groups / 中国输血杂志

【Objective】 To investigate the serological and molecular genetic characteristics of B(A) and cisAB blood groups discovered in our laboratory. 【Methods】 ABO blood group serology and genetic tests were used to identify blood groups of 6 blood samples, submitted by blood center and hospitals in Shandong, and pedigree investigation was carried on 2 of them. 【Results】 Among the 6 samples, serological results were B(A) in 5 cases and cisAB in 1 case. The results of genetic tests were consistent with the serological results, as the alleles included B(A)04, B(A)02 and cisAB01, and all genotypes were heterozygous with O. Serological pedigree study was conducted on 2 samples: One cisAB patient with his 4 relatives(cisAB type father and three O type relatives) and one B(A)02/O1 donor with his 3 relatives[ B(A) type father/brother and O type mother). For B(A)02/O1 donor, the results of genetic testing were consistent with the serological results, as the paternal genotype was the same as that of the proband, the younger brother was B(A)02/O2, and the maternal genotype was O1/O2. 【Conclusion】 The cisAB and B(A) blood groups are often indistinguishable by serological phenotypes and require genetic confirmation. CisAB pedigree investigation revealed 2 cases of cisAB blood type and B(A) pedigree investigation revealed 3 cases of B(A). The genotyping of cisAB and B(A) in this region were cisAB01/O2, B(A)02/O1, B(A)02/O2, B(A)04/O1 and B(A)04/O2. B(A)and cisAB subtypes can be accurately identified through genetic testing and pedigree investigation, which can provide a reliable basis for blood transfusion selection and ensure the safety of clinical blood transfusion.

Clinical characteristics and genetic analysis of a pedigree with Stargardt disease caused by a novel mutation in ABCA4 gene / 中华检验医学杂志

Objective:To explore the clinical characteristics and genetics of a pedigree with Stargardt disease, and investigate the pathogenicity of ABCA4 (ATP binding cassette subfamily A member 4) gene mutations in Stargardt disease.Methods:The proband was admitted to the Second People′s Hospital of Jinan in May 2021 due to diminution of vision. The proband was diagnosed with Stargardt disease according to the clinical diagnostic criteria of Stargardt disease. Detailed ophthalmological examinations was also performed on family members of the proband. Genomic DNA were extracted from the proband and the family members, and the whole exon sequencing was performed to find pathogenic gene mutations. The hazard of mutations was analyzed by polyphen-2, SIFT and MutationTaster websites. Sanger sequencing was used to verify the mutations. Conserved analysis of homologous species and 3-dimensional (3D) molecular model of the protein were used to analyze the pathogenicity.Results:Ophthalmological examinations showed reduced binocular vision, macular atrophy and "bull′s eye sign" in the proband and there was no abnormal signs and symptoms among the family members. Through whole exon sequencing analysis and Sanger sequencing verification, the compound heterozygous mutations (c.215G>A and c.6563T>C) of ABCA4 gene were co-segregated with this disease in this family. SIFT, Polyphen-2 and MutationTaster predicted that these two mutations were pathogenic. Conservative analysis and 3D molecular model of protein showed that mutations could cause changes in protein structure and affect protein function.Conclusion:The compound heterozygous mutations (C.215G>A and C.6563T>C) of ABCA4 gene are the pathogenic mutations of Stargardt disease in this pedigree.

SPTLC2 gene mutation leads to intermediate Charcot-Marries-Tooth disease: a family report / 中华神经科杂志

Objective:To report a SPTLC2 gene mutation in a family with a phenotype of Charcot-Marie-Tooth disease.Methods:To screen the family of patients with pathogenic mutations of SPTLC2 gene from the database of hereditary peripheral neuropathy in the Department of Neurology, Peking University First Hospital, and to collect their clinical data, peripheral nerve conduction examination, nerve ultrasound examination, pathological examination of the peroneal nerve and whole exome sequencing results of prohand.Results:One family was screened, the proband was a 16-year-old female with 4 years of sensory loss and anhidrosis of both lower limbs and 16 months of walking difficulty who admitted to Peking University First Hospital in January 2022. Physical examination showed sensory loss, dry skin and weakness in distal limbs. Her father had numbness and dry skin in the distal lower limbs from childhood,weakness and atrophy of his lower limbs in adulthood. He died at age of 52 years old. The nerve conduction study revealed no action potentials of the sensory and motor nerves of the lower limbs in the proband. The amplitude of the compound muscle action potential of the motor conduction of the bilateral ulnar nerve and median nerve decreased, and the nerve conduction velocity of the bilateral median nerve were 32 m/s and 24 m/s. Neurosonography showed thickening of peripheral nerves. Sural biopsy revealed severe loss of myelinated and unmyelinated nerve fibers with onion bulbs formation. SPTLC2 gene showed a known heterozygous p.G435V mutation. The lower limb weakness was improved after oral L-serine.Conclusions:SPTLC2 gene mutation can lead to an intermediate Charcot-Marie-Tooth disease phenotype. L-serine can improve the limb weakness.

Familial aggregation myelodysplastic syndromes/acute myeloid leukemia: report of 3 pedigrees and review of literature / 白血病·淋巴瘤

Objective:To investigate the clinical characteristics, gene mutation, treatment and prognosis of familial aggregation myelodysplastic syndromes/acute myeloid leukemia (MDS/AML).Methods:The 3 familial aggregation MDS/AML admitted to Shanghai Yangpu District Hospital from August 2012 to March 2019 were collected. The bone marrow examination, gene mutation detection, therapeutic effect and prognosis of the patients were retrospectively analyzed, and the relevant literature was reviewed.Results:In pedigree 1, the survival time of 2 AML patients was 8 months and 1 month, respectively. In pedigree 2, the transformation time of 2 patients diagnosed MDS to AML/high-risk MDS was 4 and 3 months, the survival time was 5 and 8 months, respectively. TP53 and RUNX1 mutations were detected in the older brother. In pedigree 3, the survival time of the AML patient was 13 months, and the MDS patient was stable.Conclusions:Familial aggregation MDS/AML has rapid progression and short survival time, and its diagnosis needs to be combined with family history, cytogenetics, and molecular biology.

A novel mutation in PAX6 gene causing congenital iris coloboma with congenital cataract in a pedigree / 中华实验眼科杂志

Objective:To identify the pathogenic gene and inheritance pattern in a pedigree of congenital iris coloboma with congenital cataract.Methods:The method of pedigree investigation was adopted.A pedigree of congenital iris coloboma with congenital cataract was collected by Yunnan Disabled Rehabilitation Center and the 2nd Afliated Hospital of Kunming Medical University in February 2020.Ophthalmic examinations were carried out on the female proband, her parents, her children and her husband, and the clinical diagnosis was made.Genomic DNA was extracted from peripheral blood samples collected from the family members.The suspected pathogenic gene in the proband and her husband was screened by whole exome sequencing and was identified by bioinformatics analysis.The amino acid conservation was analyzed by UGENE software.The impact of the mutation on protein translation was predicted using MutationTaster software.The pathogenicity of the mutation was assessed according to the American College of Medical Genetics (ACMG) Standards and Guidelines.Pathogenic gene and mutations were verified by Sanger sequencing.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the 2nd Afliated Hospital of Kunming Medical University (No.PJ-2020-61).Written informed consent was obtained from each subject or custodian.Results:The proband showed large iris defects in both eyes with only a small amount of observable iris tissue in the periphery, lens cortical opacity and posterior capsule opacification, accompanied by nystagmus.A novel heterozygous frameshift variation c. 415dupA (p.R139fs) was located in exon 8 of PAX6 gene, and the variation was conservative across multiple species.The variation was in the highly conserved region of PAX6 gene and caused the dysfunction of PAX6 protein.The variation was graded as PVS1+ PM2+ PP1, a pathogenic variation, based on ACMG guidelines.The pedigree was consistent with co-segregation, indicating that the novel variation was pathogenic.The proband and her children were diagnosed, but her parents were phenotypically normal, in accordance with autosomal dominant inheritance. Conclusions:The novel frameshift variation c.415dupA (p.R139fs) on the exon 8 of PAX6 gene is responsible for congenital iris coloboma with congenital cataract in the pedigree.This is the first report of this novel variation in PAX6 gene.

Genetic analysis of a Chinese family with cataract-microcornea syndrome / 中华实验眼科杂志

Objective:To analyze the clinical and molecular genetic characteristics of a Chinese family with congenital cataract-microcornea syndrome.Methods:The method of pedigree investigation was adopted.A Chinese Han family with congenital cataract-microcornea syndrome was recruited in Xiamen Eye Center of Xiamen University.All the family members received detailed ophthalmologic examination including the best corrected visual acuity, intraocular pressure measurement by handheld applanation tonometry, slit lamp biomicroscopy, color fundus photography, B-scan ultrasonography, corneal diameter, anterior segment optical coherence tomography, ultrasound biomicroscopy, corneal endoscopy, and corneal topography.Genomic DNA was extracted from peripheral venous blood from some patients and unaffected family members.Targeted high-throughput DNA sequencing was performed on the proband.The sequencing chip contained 188 known pathogenic genes related to lens abnormalities.Suspected pathogenic genes were verified by Sanger sequencing in phenotypically normal family members to identify the co-segregation and the disease-causing gene.Bioinformatics analysis was performed to analyze the pathogenicity of variants by REVEL.Conserved protein domains were analyzed by InterPro.Physicochemical property of the mutant protein was analyzed by ProtParam.The deleteriousness of the protein was predicted by PolyPhen-2.Homology of the variants in pathogenic gene was analyzed by NCBI website to compare the conservation among various species.This study followed the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Xiamen Eye Center of Xiamen University (No.XMYKZX-LW-2009-003).Written informed consent was obtained from each subject prior to entering the study cohort.Results:There were 39 members of 4 generations in this family including 11 patients with an autosomal dominant inheritance pattern.Clinical features of the patients included congenital cataract and microcornea.No obvious abnormality was found in ophthalmic and general examination.A heterozygous mutation c. 61C>T in the CRYAA gene was found, resulting in the mutation of the amino acid from arginine to tryptophan (p.Arg21Trp) at position 21, consistent with co-segregation.The number of cationic cluster in the mutant protein decreased, and the hydrophilicity and stability were reduced.The variant was predicted to be deleterious and was highly conserved in multiple species. Conclusions:A novel heterozygous mutation c.61C>T p. Arg21Trp in CRYAA gene is considered as the causal gene of this family.It is the first time this variant has been reported in China.

Clinical and genetic features of a Chinese family with ATF6-associated achromatopsia / 中华实验眼科杂志

Objective:To identify the clinical characteristics and pathogenic gene of a Chinese Han family with achromatopsia (ACHM).Methods:The method of pedigree investigation was adopted.A Chinese Han ACHM family was recruited in Peking Union Medical College Hospital form July 2010 to July 2019, including 5 members of 2 generations.There were 2 patients and 3 phenotypically normal individuals.The medical history was collected and comprehensive ophthalmic examinations were performed, including visual acuity, colour vision, color fundus photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), visual field and electroretinogram (ERG).Genomic DNA was extracted from peripheral blood sample from the patients and family members.Pathogenic variant was screened by whole exome sequencing (WES) and verified by Sanger sequencing and co-segregation analysis.The variant was annotated with the 1000 Genomes, Human Gene Mutation Database (HGMD), ExAC, ClinVar and OMIM databases to detect the single nucleotide polymorphism and whether it had been reported previously.The pathogenicity of the variant was evaluated according to the standards and guidelines of the American College of Medical Genetics and Genomics (ACMG).This study adhered to the Declaration of Helsinki.The study protocol was approved by the Institutional Review Board of Peking Union Medical College Hospital (No.JS-2059).Written informed consent was obtained from the guardians of juvenile patients.Results:There was consanguinity between the proband's parents and this family was consistent with autosomal recessive inheritance.Both male patients presented the reduction of visual acuity accompanied with photophobia and color blindness since childhood.Barely visible foveal light reflex in fundus images, hypofluorescence of foveal areas in FAF images, foveal defect with disruption of ellipsoid zone and interdigitation zone in OCT images were found in both patients.Central scotoma with or without peripheral visual field defects was detected.Generally normal scotopic 0.01, 3.0 and 10.0 responses, decreased oscillatory potentials amplitudes, no photopic 3.0 and 30 Hz flicker responses were observed.No sign of progression was found during the 9-year follow-up.It was confirmed that both patients carried a novel homozygous disease-causing variant c. 947insA (p.Asn316Lysfs*46) in ATF6 gene.Their mother had the heterozygous variant.The unaffected brother did not carry the variant.This family was consistent with co-segregation.This variant was labeled as pathogenic according to the ACMG standards and guidelines. Conclusions:A novel variant c.947insA (p.Asn316Lysfs*46) in ATF6 gene is the pathogenic variant of this achromatopsia family.This is the first time that this variant has been reported.

Clinical and genetic characteristics of a Han Chinese family with autosomal recessive enhanced S-cone syndrome / 中华实验眼科杂志

Objective:To analyze the clinical phenotypes and pathogenic gene of a Han Chinese family with enhanced S-cone syndrome (ESCS).Methods:The method of pedigree investigation was adopted.A suspected ESCS Han Chinese family including 8 members of 3 generations was recruited in Henan Eye Hospital from June to September 2021.There was one patient in the family.A thorough ophthalmic examination of the proband was carried out to evaluate the phenotypes, including visual acuity, degree of strabismus, anterior segment and fundus, autofluorescence imaging, fluorescein fundus angiography, full-field electroretinogram (ERG), multifocal ERG, optical coherence tomography.DNA was extracted from peripheral blood samples from the proband and family members.The pathogenic gene and variation were screened by whole exome sequencing (WES).The variation and co-segregation were verified by Sanger sequencing.The deleteriousness of the variation was analyzed by SIFT, Polyphen2 and MutationTaster.The pathogenicity of the variation was evaluated in accordance with the American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines.The analysis of amino acid sequence conservation was performed by SIFT.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Henan Eye Hospital (No.HNEECKY-2017[6]).Written informed consent was obtained from each subject.Results:This pedigree was consistent with autosomal recessive inheritance.The proband had clinical features such as night blindness, hyperopia, accommodative esotropia, peripheral retinal pigmentation, retinoschisis, and photopic ERG responses dominated by large-amplitude waves.Variations including a compound heterozygous variation, c.671C>T: p.S224L on exon 5 and c. 955G>A: p.E319K on exon 6 of NR2E3 were identified by WES.The variations were confirmed to be consistent with co-segregation.The both loci were missense variations, the variation frequency of which was 0 in the East Asian population via the gnomAD database.The variations were predicted to be deleterious by SIFT, Polyphen2 and MutationTaster.The c.671C>T variation was recorded with unknown significance in ClinVar database, and the c.955G>A variation was an unreported new locus.According to the ACMG Standards and Guidelines, the both variations were labeled as with uncertain clinical significance, and the corresponding amino acid sequences were highly conservative across multiple species. Conclusions:This family has the clinical characteristics of ESCS and meets the genetic diagnosis criteria.Two novel variations in NR2E3 gene, c.671C>T: p.S224L and 955G>A: p.E319K, are found.

Identification of a COL2A1 mutation in a Chinese family with Stickler syndrome type 1 via whole exome sequencing / 中华实验眼科杂志

Objective:To identify the disease-causing mutation in a Chinese family with Stickler syndrome type 1.Methods:The pedigree investigation was conducted.A Chinese family with Stickler syndrome type 1 was enrolled in the Shantou International Eye Center in June 2012.Medical history collection and clinical examinations, such as vision, intraocular pressure, slit lamp microscopy and fundus, were carried out in all the included family members and the diagnosis was made by clinical experts.Total genomic DNAs were extracted from the peripheral blood samples (5 ml) obtained from 5 patients and 4 healthy members.The potential variant of the proband's father Ⅲ-5 were screened by whole exome sequencing (WES) and stepwise bioinformatic analysis.The segregation and mutation conformation of the variant was verified by Sanger sequencing.The pathogenicity of the variant was predicted by SIFT, Polyphen2, and MutationTaster.Conservation and three-dimensional structure of amino acid mutation were analyzed by multiple sequence alignment and UniProt.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Joint Shantou International Eye Center (No.EC20110310[2]-P02).Written informed consent was obtained from each subject or the guardian.Results:An autosomal dominant inherence in 39 members of 4 generations including 15 patients and 24 phenotypically normal members was found in the family.The proband (Ⅳ-4) showed high myopia, retinal detachment and strabismus in the right eye, and the left eye was blind.A patient (Ⅲ-5) showed high myopia and cataract in the right eye, atrophy in the left eye.A patient (Ⅳ-9) showed binocular high myopia.A heterozygous variation, c.1693C>T: p.Arg565Cys, within the exon 26 of COL2A1 gene was revealed in patient Ⅲ-5, which was only found in the patients and not in phenotypically normal members, indiacating co-separation in this family.The variant was predicted to be a severe damage by SIFT, Polyphen2 and MutationTaster.The amino acid mutation at position 565 was highly conservative among human, mouse, rat, bovine and Xenopus laevis, which caused the arginine to cysteine substitution at the X position in triple helix repeat region Gly-X-Y, affecting the function of fibrous protein and becoming pathogenic. Conclusions:Variant c.1693C>T: p.Arg565Cys in COL2A1 gene is disease-causing in this family and this is the first report about the variant in China.

Screening of pathogenic mutation in a family with Axenfeld-Rieger syndrome by whole exome sequencing / 中华实验眼科杂志

Objective:To identify disease-causing variation in a Chinese family with Axenfeld-Rieger syndrome (ARS) through the analysis of clinical symptoms and hereditary information.Methods:The method of pedigree investigation was adopted.A Chinese ARS family including 15 family members of 3 generations was recruited in the Second Affiliated Hospital of Harbin Medical University in 2018.There were 3 patients in the family.The family history and clinical data were collected.Ophthalmic and general examinations were carried out in all the members included.DNA and RNA were extracted from collected peripheral venous blood samples of 2-5 ml from each member.Whole exome sequencing was used to screen the variations in the proband.Suspected variations screened through searching population databases and bioinformatics analysis were verified by Sanger sequencing and real-time quantitative PCR.Conservation analysis and deleteriousness prediction of suspected variations were conducted.The pathogenecity of candidate rare variations were evaluated according to the American College of Medical Genetics and Genomics (ACMG) standards and guidelines.This study followed the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the Second Affiliated Hospital of Harbin Medical University (No.KY2019-231).Written informed consent was obtained from each subject or custodian prior to entering the study cohort.Results:The 3 patients all had typical ARS clinical features in eyes, teeth and umbilicus, and carried the same heterozygous variant, c.525delC (p.Asp175Glufs *) in the PITX2 gene, which were not found in other members, indicating co-segregation.The relative expression of PITX2 mRNA was 0.672±0.063 in the patients, which was significantly lower than 1.015±0.179 in the healthy controls ( t=8.847, P<0.001).This variant was not recorded in dbSNP, 1000G, gnomeAD, ExAC, Korea1K and EVS databases, and it was labelled as deleterious by MutationTaster.The affected conservative amino acid sequences were found in 9 species.The variant was determined as pathogenic according to the ACMG standards and guidelines. Conclusions:The c.525delC (p.Asp175Glufs *) mutation of PITX2 gene is pathogenic in the pedigree.This is the first time that this mutation has been reported in Chinese family with ARS.

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.

Clinical and molecular genetics research of a Chinese Han family with Wagner syndrome / 中华实验眼科杂志

Objective:To explore the clinical features and pathogenic causes of a Chinese Han family with Wagner syndrome, and to analyze the relationship between VCAN gene mutation and patient phenotype. Methods:The method of family pedigree investigation was adopted.A Chinese Han family with Wagner syndrome in 3 generations including 13 family members was collected in Xiamen Eye Center of Xiamen University in January 2020, and 5 patients from 3 generations were diagnosed.All members underwent a comprehensive medical history collection and routine ophthalmological examinations, including visual acuity, intraocular pressure, slit lamp microscopy, and ophthalmoscopy to analyze the condition of anterior segment and fundus.Anterior segment photography, fundus photography, optical coherence tomography and ultrasound biological microscopy were carried out in the proband and some patients to analyze the condition of anterior segment, fundus and anterior chamber angle.The peripheral venous blood of all family members was collected for genomic DNA extraction, and pathogenic gene variation analysis for verification was through high-throughput target region capture sequencing and Sanger sequencing.Variants were scored using the American College of Medical Genetics and Genomics (ACMG) guidelines, and the structure and function of variants were predicted through PredictProtein.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Xiamen Eye Center of Xiamen University (No.MR-35-22-002800).Written informed consent was obtained from each subject.Results:The Chinese pedigree with Wagner syndrome was in accordance with autosomal dominant inheritance pattern, and all patients had no history of systemic disease or other abnormal manifestations.The common ophthalmic features of the patients were abnormal suspensory ligament, premature cataract, vitreous cavity, vitreous condensation, veil-like proliferative membrane in the vitreous cavity, retinal choroid atrophy and thinning, tractional retinal detachment, and retinal pigmentation.The proband had binocular cataract surgery, and binocular intraocular lens dislocation occurred after the operation.Genetic analysis revealed that a heterozygous splice site variation c.9265+ 1G>A in the VCAN gene in this family was co-segregated with the disease phenotype and graded as a likely pathogenic variant by the ACMG guidelines.This variant base pair substitution could cause the formation of a protein product with 1 754 amino acids shorter, resulting in insufficient haploid dosage and severe reduction of glycosaminoglycan attachment sites, making the versican protein dysfunctional. Conclusions:It is the first time to report a Chinese family with Wagner syndrome in China, and it is confirmed that the family has a heterozygous variation in the VCAN gene c.9265+ 1G>A by molecular genetic analysis.

Preimplantation genetic testing and prenatal diagnosis in a family with type Ⅰ neurofibromatosis / 中华围产医学杂志

We report the implantation genetic testing and prenatal diagnosis of a family with neurofibromatosis type I (NF1). High-throughput sequencing combined with multiplex ligation-dependent probe amplification was performed to identify the pathogenic mutation sites, then verified by Sanger sequencing. The pathogenic mutation of c.4172G>C in the NF1 gene was found in the proband and his mother. After sequencing and single nucleotide polymorphism (SNP) haplotyping of the mutation sites in the embryos by establishing the SNP-linked haplotype, a well-developed blastocyst, without pathogenic mutations, was transplanted, and 28 d later, the ultrasound confirmed that the patient was pregnant. Amniotic fluid samples of the fetus were obtained at 19 +3 weeks for karyotyping and detection of the gene mutation site, which found the fetus did not carry the maternal c.4172G>C mutation of NF1 gene or any copy number variants of clear clinical significance. The patient delivered a healthy term girl by cesarean section, and no significant abnormalities were found during the follow-up to 10 months of age.

DYNC2H1 gene mutation analysis and prenatal diagnosis in two pedigrees affected with short rib-polydactyly syndrome type Ⅲ / 中华围产医学杂志

Objective:To investigate the molecular genetic etiology of two fetuses with short rib-polydactyly syndrome type Ⅲ (SRPS Ⅲ).Methods:Next-generation sequencing (NGS) was used to detect 226 known genes related to inherited skeletal dysplasia in two fetuses with SRPS Ⅲ diagnosed in the First Affiliated Hospital of Zhengzhou University in August 2015 and June 2020. Suspect pathological variants were verified in the pedigree members using Sanger sequencing. The prenatal genetic diagnosis of the high-risk fetus in pedigree one was conducted to identify the confirmed pathogenic variation.Results:The homozygous mutation of DYNC2H1 gene c.5881A>G(p.Lys1961Glu) was identified in the proband in pedigree one, and the parents were the carriers. The proband in pedigree two carried compound heterozygous mutations in the DYNC2H1 gene with c.10606C>T(p.Arg3536*) inherited from the father and c.8954T>G(p.Val2985Gly) from the mother. Autosomal recessive inheritance was confirmed in both pedigrees. Mutations of c.5881A>G(p.Lys1961Glu) and c.8954T>G(p.Val2985Gly) in the DYNC2H1 gene were likely pathogenic variants and had not been reported before. The prenatal diagnosis did not identify the DYNC2H1 gene c.5881A>G(p.Lys1961Glu) mutation in the fetus (Ⅱ-7) in pedigree one, which was confirmed by the umbilical cord blood sample after birth. Conclusion:DYNC2H1 gene mutation underlies the fetal skeletal dysplasia in the two pedigrees.