scholarly journals Novel SOX2 Mutation in Autosomal Dominant Cataract-Microcornea Syndrome

Author(s):  
Zhi-Bo Lin ◽  
Jin Li ◽  
Hai-Sen Sun ◽  
A-Yong Yu ◽  
Shi-Hao Chen ◽  
...  

Abstract Background: Congenital cataract-microcornea syndrome (CCMC) is characterized by the association of congenital cataract and microcornea without any other systemic anomaly or dysmorphism. Although several causative genes have been reported in patients with CCMC, the genetic etiology of CCMC is yet to be clearly understood. Purpose: To unravel the genetic cause of autosomal dominant family with CCMC.Methods: All patients and available family members underwent a comprehensive ophthalmologic clinical examination in the hospital by expert ophthalmologists and carried out to clinically diagnosis. All the patients were screened by whole-exome sequencing and then validated using co-segregation by Sanger sequencing. Results: Four CCMC patients from a Chinese family, and five unaffected family members were enrolled in this study. Using whole-exome sequencing, missense mutation c.295G>T (p.a99s, NM_003106.4) in the SOX2 gene was identified and validated by segregation analysis. In addition, this missense mutation was predicted to be damaging by multiple predictive tools. Variant p.Ala99Ser was located in a conservation high mobility group (HMG)-box domain in SOX2 protein, with a potential pathogenic impact of p.Ala99Ser on protein level.Conclusions: A novel missense mutation (c.295G>T, p.Ala99Ser) in the SOX2 gene was found in this Han Chinese family with congenital cataract and microcornea. Our study firstly determined that mutations in SOX2 were associated with CCMC, warranting further investigations on the pathogenesis of this disorder. This result expands the mutation spectrum of SOX2 and provides useful information to study the molecular pathogenesis of CCMC.

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Yu Zhou ◽  
Yaru Zhai ◽  
Lulin Huang ◽  
Bo Gong ◽  
Jie Li ◽  
...  

Congenital cataract is the most common cause of the visual disability and blindness in childhood. This study aimed to identify gene mutations responsible for autosomal dominant congenital cataract (ADCC) in a Chinese family using next-generation sequencing technology. This family included eight unaffected and five affected individuals. After complete ophthalmic examinations, the blood samples of the proband and two available family members were collected. Then the whole exome sequencing was performed on the proband and Sanger sequencing was applied to validate the causal mutation in the two family members and control samples. After the whole exome sequencing data were filtered through a series of existing variation databases, a heterozygous mutation c.499T<G (p.E167X) in CRYBB2 gene was found. And the results showed that the mutation cosegregated with the disease phenotype in the family and was absolutely absent in 1000 ethnicity-matched control samples. Thus, the heterozygous mutation c.499T<G (p.E167X) in CRYBB2 was the causal mutation responsible for this ADCC family. In conclusion, our findings revealed a novel stopgain mutation c.499T<G (p.E167X) in the exon 6 of CRYBB2 which expanded the mutation spectrum of CRYBB2 in Chinese congenital cataract population and illustrated the important role of CRYBB2 in the genetics research of congenital cataract.


2020 ◽  
pp. 014556132091062
Author(s):  
Yongli Zhang ◽  
Qi Tang ◽  
Ruoyan Xue ◽  
Xiaohui Zhu ◽  
Hua Yang ◽  
...  

Background: Otosclerosis is a focal lesion of the inner ear. The role of genetic factors in the pathogenesis of otosclerosis has received increasing attention. We analyzed the clinical manifestations, inheritance pattern, and pathogenic genes in a family with otosclerosis. Methods: We collected clinical data and generated a family pedigree. High-throughput second-generation sequencing technology was used to identify candidate genes by performing whole-exome sequencing of 7 members of the family, and Sanger sequencing was performed to validate candidate gene mutations in the 7 family members. Results: Otosclerosis was characterized by autosomal dominant inheritance in this family. Whole-exome sequencing did not reveal mutation sites in known deafness-related genes. However, a c.2209A > G (p.T737A) mutation was detected in exon 6 of the SP1 gene, which is associated with the COL1A1 gene. This mutation was a pathogenic mutation, and Sanger sequencing confirmed that this mutation cosegregated with the clinical phenotype among the family members. Conclusions: The pattern of otosclerosis in this family is consistent with autosomal dominant inheritance, and the SP1 gene, harboring the c.2209A > G (p.T737A) mutation in exon 6, may be the causative gene of otosclerosis in this family.


2020 ◽  
Vol 40 (5) ◽  
Author(s):  
Handong Dan ◽  
Tuo Li ◽  
Xinlan Lei ◽  
Xin Huang ◽  
Yiqiao Xing ◽  
...  

Abstract Choroideremia is a complex form of blindness-causing retinal degeneration. The aim of the present study was to investigate the pathogenic variant and molecular etiology associated with choroideremia in a Chinese family. All available family members underwent detailed ophthalmological examinations. Whole exome sequencing, bioinformatics analysis, Sanger sequencing, and co-segregation analysis of family members were used to validate sequencing data and confirm the presence of the disease-causing gene variant. The proband was diagnosed with choroideremia on the basis of clinical manifestations. Whole exome sequencing showed that the proband had a hemizygous variant in the CHM gene, c.22delG p. (Glu8Serfs*4), which was confirmed by Sanger sequencing and found to co-segregate with choroideremia. The variant was classified as likely pathogenic and has not previously been described. These results expand the spectrum of variants in the CHM gene, thus potentially enriching the understanding of the molecular basis of choroideremia. Moreover, they may provide insight for future choroideremia diagnosis and gene therapy.


2022 ◽  
Vol 12 ◽  
Author(s):  
Fengyu Che ◽  
Jiangang Zhao ◽  
Yujuan Zhao ◽  
Zhi Wang ◽  
Liyu Zhang ◽  
...  

Aim: To determine the etiology of a Chinese family with thrombocytopenia by analyzing the clinical features and genetic variation.Methods: Clinical profiles and genomic DNA extracts of the family members were collected for the study. Whole exome sequencing and Sanger sequencing was used to detect the associated genetic variation and verify the family co-segregation respectively. Bioinformatics analysis assessed the pathogenicity of missense mutations.Results: The study reported a 3-generation pedigree including eight family members with thrombocytopenia. The platelet counts of the patients were varied, ranging from 38 to 110 × 109/L (reference range: 150–450 x 109/L). The mean volumes and morphology of the sampled platelet were both normal. The bleeding abnormality and mitochondriopathy were not observed in all the patients. Clinical signs of thrombocytopenia were mild. A novel heterozygous missense variant c.79C &gt; T (p.His27Tyr) was identified in CYCS gene associated with autosomal dominant thrombocytopenia.Conclusion: We report the first large family with autosomal dominant non-syndromic thrombocytopenia 4 in a Chinese family, a novel heterozygous missense variant c.79C &gt; T (p.His27Tyr) was identified. The whole exome sequencing is an efficient tool for screening the variants specifically associated with the disease. The finding enriches the mutation spectrum of CYCS gene and laid a foundation for future studies on the correlation between genotype and phenotype.


2018 ◽  
Author(s):  
Guohui Liu ◽  
Ziying Yang ◽  
Weiwei Chen ◽  
Junguang Xu ◽  
Liangwei Mao ◽  
...  

PurposeCardiovascular diseases are the most common cause of death globally. In which atrioventricular block (AVB) is a common disorder with genetic causes, but the responsible genes have not been fully identified yet. To determine the underlying causative genes involved in cardiac AVB, here we report a three-generation Chinese family with severe autosomal dominant cardiac AVB that has been ruled out as being caused by known genes mutations.MethodsWhole-exome sequencing was performed in five affected family members across three generations, and co-segregation analysis was validated on other members of this family.ResultsWhole-exome sequencing and subsequent co-segregation validation identified a novel germline heterozygous point missense mutation, c.49287C>A (p.N16429K), in the titin (TTN, NM_001267550.2) gene in all 5 affected family members, but not in the unaffected family members. The point mutation is predicted to be functionally deleterious by in-silico software tools. Our finding was further supported by the conservative analysis across species.ConclusionBased on this study, TTN was identified as a potential novel candidate gene for autosomal dominant AVB; this study expands the mutational spectrum of TTN gene and is the first to implicate TTN mutations as AVB disease causing in a Chinese pedigree.


Author(s):  
Qing Li ◽  
Chengfeng Wang ◽  
Wei Li ◽  
Zaiqiang Zhang ◽  
Shanshan Wang ◽  
...  

AbstractPontine autosomal dominant microangiopathy and leukoencephalopathy (PADMAL) is a rare hereditary cerebral small vessel disease. We report a novel collagen type IV alpha 1 (COL4A1) gene mutation in a Chinese family with PADMAL. The index case was followed up for 6 years. Neuroimaging, whole-exome sequencing, skin biopsy, and pedigree analysis were performed. She initially presented with minor head injury at age 38. MRI brain showed chronic lacunar infarcts in the pons, left thalamus, and right centrum semiovale. Extensive workup was unremarkable except for a patent foramen ovale (PFO). Despite anticoagulation, PFO closure, and antiplatelet therapy, the patient had recurrent lacunar infarcts in the pons and deep white matter, as well as subcortical microhemorrhages. Whole-exome sequencing demonstrated a novel c.*34G > T mutation in the 3′ untranslated region of COL4A1 gene. Skin biopsy subsequently demonstrated thickening of vascular basement membrane, proliferation of endothelial cells, and stenosis of vascular lumen. Three additional family members had gene testing and 2 of them were found to have the same heterozygous mutation. Of the 18 individuals in the pedigree of 3 generations, 12 had clinical and MRI evidence of PADMAL. The mechanisms of both ischemic and hemorrhagic stroke are likely the overexpression of COLT4A1 in the basement membrane and frugality of the vessel walls. Our findings suggest that the novel c.*34G > T mutation appears to have the same functional consequences as the previously reported COL4A1 gene mutations in patients with PADMAL and multi-infarct dementia of Swedish type.


2018 ◽  
Vol 103 (6) ◽  
pp. 761-767 ◽  
Author(s):  
Laura Bryant ◽  
Olga Lozynska ◽  
Anson Marsh ◽  
Tyler E Papp ◽  
Lucas van Gorder ◽  
...  

BackgroundVariants in PRPF31, which encodes pre-mRNA processing factor 31 homolog, are known to cause autosomal-dominant retinitis pigmentosa (adRP) with incomplete penetrance. However, the majority of mutations cause null alleles, with only two proven pathogenic missense mutations. We identified a novel missense mutation in PRPF31 in a family with adRP.MethodsWe performed whole exome sequencing to identify possible pathogenic mutations in the proband of a family with adRP. Available affected family members had a full ophthalmological evaluation including kinetic and two-colour dark adapted static perimetry, electroretinography and multimodal imaging of the retina. Two patients had evaluations covering nearly 20 years. We carried out segregation analysis of the probable mutation, PRPF31 c.590T>C. We evaluated the cellular localisation of the PRPF31 variant (p.Leu197Pro) compared with the wildtype PRPF31 protein.ResultsPRPF31 c.590T>C segregated with the disease in this four-generation autosomal dominant pedigree. There was intrafamilial variability in disease severity. Nyctalopia and mid-peripheral scotomas presented from the second to the fourth decade of life. There was severe rod >cone dysfunction. Visual acuity (VA) was relatively intact and was maintained until later in life, although with marked interocular asymmetries. Laboratory studies showed that the mutant PRPF31 protein (p.Leu197Pro) does not localise to the nucleus, unlike the wildtype PRPF31 protein. Instead, mutant protein resulted in punctate localisation to the cytoplasm.Conclusionsc.590T>C is a novel pathogenic variant in PRPF31 causing adRP with incomplete penetrance. Disease may be due to protein misfolding and associated abnormal protein trafficking to the nucleus.


2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Qin Xiang ◽  
Lamei Yuan ◽  
Yanna Cao ◽  
Hongbo Xu ◽  
Yunfeiyang Li ◽  
...  

Background/Aims. Corneal dystrophies (CDs) belong to a group of hereditary heterogeneous corneal diseases which result in visual impairment due to the progressive accumulation of deposits in different corneal layers. So far, mutations in several genes have been responsible for various CDs. The purpose of this study is to identify gene mutations in a three-generation Hui-Chinese family associated with granular corneal dystrophy type I (GCD1). Methods. A three-generation Hui-Chinese pedigree with GCD1 was recruited for this study. Slit-lamp biomicroscopy, optical coherence tomography, and confocal microscopy were performed to determine the clinical features of available members. Whole exome sequencing was performed on two patients to screen for potential disease-causing variants in the family. Sanger sequencing was used to test the variant in the family members. Results. Clinical examinations demonstrated bilaterally abundant multiple grayish-white opacities in the basal epithelial and superficial stroma layers of corneas of the two patients. Whole exome sequencing revealed that a heterozygous missense mutation (c.1663C > T, p.Arg555Trp) in the transforming growth factor beta-induced gene (TGFBI) was shared by the two patients, and it cosegregated with this disease in the family confirmed by Sanger sequencing. Conclusions. The results suggested that the heterozygous TGFBI c.1663C > T (p.Arg555Trp) mutation was responsible for GCD1 in the Hui-Chinese family, which should be of great help in genetic counseling for this family.


2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Yue Zhang ◽  
Manhong Xu ◽  
Minglian Zhang ◽  
Guoxing Yang ◽  
Xiaorong Li

Bardet-Biedl syndrome (BBS) is a genetically heterogeneous disorder characterized by polydactyly, obesity, rod-cone dystrophy, and mental retardation. Twenty-one genes have been identified as causing BBS. This study collected a BBS pedigree from two patients and performed whole-exome sequencing on one patient. We identified a novel homozygous variant c.1114C>T (p.Q372X) in the BBS9 of the two siblings. This variant was confirmed and completely cosegregated with the disease of this family by Sanger sequencing. We report a novel homozygous variant c.1114C>T in the BBS9 gene in a Chinese family.


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