A Research Of Disease Genes In A Congenital Cataract Family

Objectives:Congenital cataract is a children’s common eye disease which leads to amblyopia and even blindness dues to abnormal development of embryonic lens that contributes to lens opacity.Congenital cataract accounts for approximately 10% of children’s blinding eye disease.The feature of particular populations,various hereditary modes,difficulty in early detection,limitations of treatment and poor effect of surgeries make it urgent to discover its pathogenesis on gene level.The worldwide scholars have discovered 20 congenital cataract related genes using sequencing and chip technologies.Our research focused on a congenital cataract family from Xishuangbanna Autonomous Prefecture of Yunnan province. We applied microarrays to scan their whole genome to analyze copy number variation(CNV) and then determine the candidate genes whose relative biological information were then excavated to analyze their potential roles in congenital cataract.Meanwhile,it is better to supplement the disease genes pool of congenital cataract and explore the relationship between genotype and phenotype of the disease.Methods:1.We collected a hereditary congenital cataract family from Xishuangbanna Autonomous Prefecture of Yunnan province in Ophthalmology Department of No.4 affiliated hospital of Kunming Medical University.2.After collecting relative clinical materials and recording familial details including total family members,the numbers of familial patients and their distribution in each generation,we analyzed their genetic genealogy and confirmed the genetic mode.3.Overall health and comprehensive ophthalmic examinations of the eight family members have been carried out to determine their types of cataract.4.Peripheral venous bloods of the eight family members were collected to extract DNA using PerfectPure DNA Blood Kit(5 PRIME).Polymerase chain reaction was achieved by using GeneAmp(?)PCR9700 system.The 2% agarose gel electrophoresis was used to verify whether PCR productions molecular weight was between 150bp-20000bp.5.We hybridized purified and fragmented PCR productions together with microarrays and performed microarray scanner to generate data.6.Bioinformatics software such as MAS3.0,GO et al were applied to analyze CNV information and excavate potential signaling pathways those mutated genes may have been involved in. Prediction of possible gene networks and protein networks were also achieved in our study.Results:1.The inheritance mode of congenital cataract of our target family is autosomal dominant inheritance.2. We filtered 33 of the most typical CNV regions which include two regions of CNV gain and 31 CNV loss regions.Then 25 corresponding candidate genes are selected.3.After analyzing their biological information we find that these involved genes participate in protein binding,zinc ion binding protein, nucleotide binding, ATP-binding protein, transcriptional repressor, the activity of tyrosine phosphatase transmembrane receptor and DNA.Besides,they are also involved in DNA-dependent transcription regulation, fatty acid biosynthesis, cell adhesion, cell cycle, cellular redox balance, cell mitosis, DNA damage repair, morphology organ formation, protein hydrolysis, metabolism and other biological processes.4.Our study has detected some brand-new mutated genes relate to congenital cataract which provide the theoretical basis for a new direction in our future research.Conclusions:Our research suggested that CNV might potentially be important for hereditary congenital cataract,and could be a genetic susceptibility markers of congenital cataract.