Detection of pathogenic gene mutations in thirteen cases of congenital bilateral absence of vas deferens infertility patients
10.19723/j.issn.1671-167X.2024.05.003
- VernacularTitle:13例先天性双侧输精管缺如不育患者的致病基因突变检测
- Author:
Ying TANG
1
;
Yongbo ZHANG
;
Danhong WU
;
Yanhong LIN
;
Fenghua LAN
Author Information
1. 福建省移植生物学重点实验室,福建医科大学福总临床医学院(第九○○医院),福州 350025
- Keywords:
Congenital bilateral absence of the vas deferens;
Cystic fibrosis transmembrane conduc-tance regulator;
Adhesion G protein-coupled receptor G2;
Solute carrier family 9 member A3
- From:
Journal of Peking University(Health Sciences)
2024;56(5):763-774
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To detect the cystic fibrosis transmembrane transduction regulator(CFTR)gene mutations and congenital bilateral absence of vas deferens(CBAVD)susceptibility gene mutations in pa-tients with CBAVD,and to explore their association with the risk of CBAVD.Methods:Whole-exome sequencing and Sanger sequencing validation were conducted on the pathogenic genes CFTR,adhesion G protein-coupled receptor G2(ADGRG2),sodium channel epithelial 1 subunit beta(SCNN1B),carbonic anhydrase 12(CA12),and solute carrier family 9 member A3(SLC9A3)in thirteen cases of isolated CBAVD patients.The polymorphic loci,intron and flanking sequences of CFTR gene were amplified by polymerase chain reaction(PCR)followed by Sanger sequencing.Bioinformatics methods were employed for conservative analysis and deleterious prediction of novel susceptibility gene mutations in CBAVD.Ge-netic analysis was performed on the pedigree of one out of thirteen patients with CBAVD to evaluate the risk of inheritance in offspring.Results:Exome sequencing revealed CFTR gene exon mutations in only six of the thirteen CBAVD patients,with six missense mutations c.2684G>A(p.Ser895Asn),c.4056G>C(p.Gln1352His),c.2812G>(p.Val938Leu),c.3068T>G(p.Ile1023Arg),c.374T>C(p.Ile125Thr),c.1666A>G(p.Ile556Val)),and one nonsense mutation(c.1657C>T(p.Arg553Ter).Among these six patients,two also had the CFTR homozygous p.V470 site,additional-ly,mutations in CFTR gene exon regions were not detected in the remaining seven patients.Within the thirteen CBAVD patients,three carried the homozygous p.V470 polymorphic site,four carried the 5T al-lele,two carried the TG13 allele,and ten carried the c.-966T>G site.Four CBAVD patients simulta-neously carried 2-3 of the aforementioned CFTR gene mutation sites.Susceptibility gene mutations in CBAVD among the thirteen patients included one ADGRG2 missense mutation c.2312A>G(p.Asn771Ser),two SLC9A3 missense mutations c.2395T>C(p.Cys799Arg),c.493G>A(p.Val165Ile),one SCNN1B missense mutation c.1514G>A(p.Arg505His),and one CA12 missense mutation c.1061C>T(p.Ala354Val).Notably,the SLC9A3 gene c.493 G>A(p.Val165Ile)mutation site was first identi-fied in CBAVD patients.The five mutations exhibited an extremely low population mutation frequency in the gnomAD database,classifying them as rare mutations.Predictions from Mutation Taster and Poly-phen-2 software indicated that the harmfulness level of the SLC9A3 gene c.493G>A(p.Val165Ile)site and the SCNN1B gene c.1514G>A(p.Arg505His)site were disease causing and probably damaging.The genetic analysis of one pedigree revealed that the c.1657C>T(p.Arg553Ter)mutation in the proband was a de novo mutation,as neither the proband's father nor mother carried this mutation.The proband and his spouse conceived a daughter through assisted reproductive technology,and the daughter inherited the proband's pathogenic mutation c.1657C>T(p.Arg553Ter).Conclusion:CFTR gene mutations remain the leading cause of CBAVD in Chinese patients;however,the distribution and fre-quency of mutations differ from data reported in other domestic and international studies,highlighting the need to expand the CFTR mutation spectrum in Chinese CBAVD patients.The susceptibility genes ADGRG2,SLC9A3,SCNN1B,and CA12 may explain some cases of CBAVD without CFTR mutations.Given the lack of specific clinical manifestations in CBAVD patients,it is recommended that clinicians conduct further physical examinations and consider scrotal or transrectal ultrasound before making a defi-nitive diagnosis.It is advisable to employ CFTR gene mutation testing in preconception genetic screening to reduce the risk of CBAVD and cystic fibrosis in offspring.