Sequencing of 100 common variation sites of 18 deafness susceptibility genes among 16 182 individuals from Dongguan / 中华医学遗传学杂志

OBJECTIVE@#To determine the type and carrier rate of deafness-related variants in Dongguan, China.@*METHODS@#A total of 16 182 subjects were screened. Heel blood samples were collected from newborns, while peripheral venous blood samples were collected from the remainders. For each individual, 100 variations of 18 deafness susceptibility genes were detected.@*RESULTS@#In total 1631 deafness-related variants (including 5 homozygous mutations) were detected, which gave a detection rate of 10.08%. The detection rate of SLC26A4 gene variants was the highest (845 cases, 5.22%), which was followed by GJB2 (673 cases, 4.16%), GJB3 (100 cases, 0.62%), TMC1 (12 cases, 0.07%), and MYO15A (1 case, 0.01%). The detection rate for GJB2 c.235delC variant was the highest (524 cases, 3.24%), which was followed by SLC26A4 IVS7-2A>G variant (270 cases, 1.67%). Thirty three individuals (0.20%) carried two variants at the same time, 7 of them (0.04%) carried compound heterozygous variants of the same gene.@*CONCLUSION@#To expand the range of screening can help with determination of the carrier status and provision of early intervention and genetic counseling for the examinees.

The phenotype and genotype characteristics of 41 patients with steroid 5α-reductase type 2 deficiency / 中华内分泌代谢杂志

Objective To investigate the cliuical phenotype and the genotype of forty-one patients with steroid 5α-reductase type 2 deficiency.Methods The clinical data were collected including physical examination,medical history,laboratory test,as well as ultrasonic examination.Genomic DNA was extracted from peripheral blood leukocytes.Sanger sequencing and targeted gene captured next-generation sequencing were applied to detect the SRDSA2 gene mutation.Results All the patients are Han nationality and their ages ranged from 4 months to 11 years old.The karyotypes of 41 patients were 46,XY and all SRY genes were detected as positive.There were 26 (63％) patients manifested isolated micropenis,and the rest of fifteen patients were hypospadias associated with microphallus accounting for 37％.There were 39 patients who carried biallelic mutation.Two cases just identified one allele mutation.Sixteen gene mutation types were confirmed.Among them c.725A ＞ G (p.Tyr242Cys),c.694C ＞ G (p.His232Asp),and c.548-9T＞G are the novel gene types.The allele frequency of c.680G＞A (p.Arg227Gln) is 60％ (48/80).Conclusion The primary manifestations of patients with steroid 5α-reductase type 2 deficiency were micropenis or hypospadias accompanied with micropenis.c.680G＞A (p.Arg227Gln) is the predominantly mutation type of Chinese patient with steroid 5α-reductase type 2 deficiency.