Xu Zhi-Yong, Zhang Jia-Xun, Liu Yang, Geng Qian, Xie Jian-Sheng, Li Xiao-Jun
Center of Medical Genetics, Shenzhen Maternity and Child Healthcare Hospital Affiliated to Southern Medical University, Shenzhen, Guangdong 518028, China.
Central Laboratory, Jinling Hospital, Nanjing University School of Medicine / General Hospital of Eastern Theater Command, Nanjing, Jiangsu 210002, China.
Zhonghua Nan Ke Xue. 2020 Dec;26(12):1105-1111.
To investigate the clinical characteristics and pathogenic basis of a case of 46, XY disorders of sex development (DSD) and analyze the relationship of the missense mutation with the phenotype of the LHCGR gene.
We analyzed the causative gene mutation by next-generation high-throughput sequencing (HTS) and confirmed it by Sanger sequencing. We detected the effect of the mutation on the splicing function by minigene assay, evaluated its pathogenicity using the ANNOVAR mutation annotation software, and analyzed the relationship of the missense mutation and the phenotype of the LHCGR gene via literature review and data mining.
A homozygous mutation of C.458T>C (p.Leu153Pro) was detected in the last base of exon5 of the LHCGR gene in the 46,XY DSD patient, which was a new mutation not reported previously. The mother of the patient was a heterozygous carrier of the mutation. Minigene assay indicated that c.458T>C (p.Leu153Pro) did not affect the splicing function. The mutation was shown to be pathogenic by ANNOVAR software analysis and presumed inactive, possibly affecting its binding with the ligand and leading to type-I Leydig cell hypoplasia (LCH). Literature review and data mining showed that only 19 missense mutations could cause LCH, which scattered in the LHCGR gene.
The new mutation c.458T> C (p.Leu153Pro) of the LHCGR gene found in the 46, XY DSD patient may cause LCH by interfering with the binding function of the ligand, which has enriched the LHCGR gene mutation database and provided some reference for the studies on the LCH genotype, its phenotypic correlation and gene functions.
探讨1例46, XY性发育障碍(DSD)患者的临床特征和致病基础,并分析错义突变与促黄体生成素/绒毛膜促性腺激素受体(LHCGR)基因表型的关系。
采用二代高通量测序(HTS)分析致病基因突变,并通过桑格测序进行验证。通过小基因分析检测突变对剪接功能的影响,使用ANNOVAR突变注释软件评估其致病性,并通过文献综述和数据挖掘分析错义突变与LHCGR基因表型的关系。
在46, XY DSD患者的LHCGR基因外显子5最后一个碱基处检测到纯合突变C.458T>C(p.Leu153Pro),这是一个此前未报道的新突变。患者母亲为该突变的杂合携带者。小基因分析表明c.458T>C(p.Leu153Pro)不影响剪接功能。经ANNOVAR软件分析,该突变被证明具有致病性,并推测其无活性,可能影响其与配体的结合,导致I型莱迪希细胞发育不全(LCH)。文献综述和数据挖掘显示,只有19个错义突变可导致LCH,这些突变分散在LHCGR基因中。
在46, XY DSD患者中发现的LHCGR基因新突变c.458T>C(p.Leu153Pro)可能通过干扰配体的结合功能导致LCH,丰富了LHCGR基因突变数据库,为LCH基因型、表型相关性及基因功能的研究提供了一定参考。