1.Clinical manifestations and genetic analysis of six different families of Leber's congenital amaurosis
Zhouxian BAI ; Jingzhi SHAO ; Yibing CHEN ; Xiangdong KONG
Chinese Journal of Ocular Fundus Diseases 2021;37(3):195-200
Objective:To observe and analyze the pathogenic gene types and clinical phenotypes of Leber congenital amaurosis (LCA).Methods:A retrospective clinical study. Six patients with LCA confirmed by genetic testing and 18 family members were included in the study. The patients came from six unrelated families. The family was investigated with a specific hereditary eye disease enrichment panel which contained 463 known pathogenic genes and based on targeted exome capture technology first to indentify the potential pathogenic genes and mutations. Then the TULP1 , RPGRIP1 , GUCY2D pathogenic mutations were conformed by Sanger sequencing. The pathogenicity of the gene variation was searched through relevant databases and PubMed literature, and its function was explained by protein prediction software. Results:Of the 6 patients, 3 were males and 3 were females; the age was from 3 to 33 years. Nystagmus, finger pressing eyes, photophobia, and night blindness were seen in 5 cases; electroretinogram showed 3 cases of extinction or near extinction; and 4 cases of retinopathy. The results showed patients with compound heterozygous mutation of c.1318C> T and c.1142T> G, homozygous mutation ofc.1318C> T and compound heterozygous mutation of c.1153G> A and c.1561C> T of TULP1 in Family 1, Family 2 and Family 5, respectively. There were compound heterozygous mutations of RPGRIP1 c.391delG and c.1468-2A> G in Family 3 and c.715delA and c.1765C> T in Family 6, respectively. Homozygous mutation of c.3177_3178delAC of GUCY2D was found in Family 4.The parents of all six patients were carriers of corresponding heterozygous mutations. TULP1 gene c.1142T> G, RPGRIP1 gene c.391delG, c.715delA and c.1765C> T and GUCY2D gene c.3177_3178delAC mutations were novel mutations and unreported. The 381th amino acid locus of product protein of TULP1 gene was highly conserved among species. The protein prediction software predicted that the mutation pathogenic. The c.391delG, c.715delA and c.1765C> T mutations of RPGRIP1 gene and c.3177_3178delAC mutation of GUCY2D gene can lead to early translation termination of their product proteins, which are pathogenic variants. Conclusion:The pathogenic mutations of TULP1, RPGRIP1 and GUCY2D genes led to LCA 15, LCA 6 and LCA 1 in six families.
2.The inhibitory effect of decorin on apoptosis of human lens epithelial cells under high glucose condition and its mechanism
Dandan XIE ; Shanshan DU ; Ying QI ; Jingzhi SHAO ; Fengyan ZHANG
Chinese Journal of Experimental Ophthalmology 2019;37(4):252-256
Objective To investigate the effects of decorin (DCN) on apoptosis and oxidative stress in human lens epithelial cells (LECs) under high glucose condition.Methods HLE-B3 cells were cultured in vitro and the effect of DCN with different concentrations on HLE-B3 viability was determined by using cell counting kit-8 (CCK-8).The cultured cells were divided into normal control group,DCN group,high glucose group and DCN + high glucose group.Flow cytometry was used to detect the apoptosis rate and the expression of reactive oxygen species (ROS) in the cells.Microplate spectrophotometer was used to measure total superoxide dismutase (SOD) enzyme activity and the radio of glutathione (GSH)/glutathione disulfide (GSSG).Western blot was used to detect the expressions of bax and bcl-2 proteins.Results HLE-B3 cells were spindle shaped,with centered and clearly visible nuclei and neatly cell arrangment.According to CCK-8 method,survival rates of HLE-B3 in all groups were more than 90%.Different concentrations of DCN showed no significant effect on HLEoB3 survival rate (all at P>0.05).After 48 hours of cell culture,the apoptosis rate of high glucose group was significantly higher than that of normal control group,and the apoptosis rate of DCN+high glucose group was significantly lower than that of high glucose group (both at P =0.000).The mean fluorescence intensity of intracellular ROS in the high-glucose group was significantly higher than that in the normal control group,and the mean fluorescence intensity of ROS in the DCN group was significantly higher than that in the high glucose group (both at P=0.000).The total SOD activity in the high glucose group was significantly lower than that in the normal control group and DCN group (P =0.007,0.004).The GSH/GSSG ratio of the high-glucose group was significantly lower than that of the normal control group and DCN group (both at P=0.000).Conclusions DCN can inhibit the apoptosis and oxidative stress of HLE-B3 under high glucose,which provides the basis for the treatment of diabetic cataract.
3.Gene mutation analysis of 12 families with congenital cataract
Zhouxian BAI ; Jingzhi SHAO ; Lina LIU ; Xiangdong KONG
Chinese Journal of Experimental Ophthalmology 2022;40(10):960-965
Objective:To analyze the clinical manifestations of congenital cataract in 12 families and gene variants causing the disease.Methods:The method of pedigree investigation was adopted.Clinical data of 27 patients from 12 Chinese Han families with congenital cataract were collected, and genomic DNA was extracted from peripheral blood samples of patients and family members.Candidate variants were screened by next generation sequencing and were verified by Sanger sequencing.Population frequency of the variants were obtained through the Genome Arrgregation Database (gnomAD).Pathogenicity of variants was analyzed through the Human Gene Mutation Database (HGMD), Database of Single Nucleotide Polymorphism (dbSNP) and PubMed, and the mutation effect was interpreted by protein prediction softwares including SIFT, PolyPhen_2 and MutationTaster.The conservation analysis of amino acid sequences of variants was performed by GERP+ + software.Diagnosis was confirmed by clinical ophthalmic phenotype, medical history and mutation analysis.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the First Affiliated Hospital of Zhengzhou University (No.KS-2018-KY-36).Written informed consent was obtained from all subjects and their guardians.Results:Pathogenic genetic variants were found in all the 12 families, 9 of which had known pathogenic variants including MIP c.97C>T, GJA8 c.593G>A, CRYBA4 c.277T>C, CRYBB2 c.563G>A and c.436G>C, CRYGC c.470G>A, CRYGD c.70C>A, PAX2 c.70dupG as well as OCRL E5-E16dup, and 3 novel potential pathogenic variants including CRYGD c.422delG, ELP4 c.886C>A and CRYBB2 c.434G>C. CRYGD c.422delG could lead to the early termination of translation of protein products, which was pathogenic.The nucleotide and amino acid sites of ELP4 c.886C>A and CRYBB2 c.434G>C were highly conserved among species, and were predicted as harmful.The 12 families were consistent with co-segregation. Conclusions:CRYGD c.422delG, ELP4 c.886C>A and CRYBB2 c.434G>C may be novel pathogenic variants of congenital cataract.