ADGRG2基因变异导致先天性输精管缺如的分子遗传机制研究

Congenital absence of vas deferens is one of the leading cause of obstructive azoospermia and male infertility, which is mainly comprised of bilateral absence of vas deferens (CBAVD). Recent studies have identified ADGRG2 as a new causal gene of CBAVD, and we have identified several mutations in Chinese patients. Yet, the pathogenicity of those variants still lacks functional evidence and the molecular genetic mechanism remains unclear. Here, we will firstly explore the influence of variants on the functions of ADGRG2, CFTR and downstream pathways by cell experiments. Then, we will observe the change of efferent ductules morphology and fertility of site-directed mutated and knock-out mice, and elucidate the related mechanism. Our study will provide more evidence in understanding the development of CBAVD.

先天性输精管缺如是导致男性不育的重要原因之一，其中以双侧输精管缺如为主（CBAVD）。近期研究发现ADGRG2是新的CBAVD致病基因，本课题组前期也在中国人群中识别出了ADGRG2新致病突变。但是国内外已发现的ADGRG2突变致病性及其分子遗传机制仍缺乏关键的功能试验证据。本课题将分别通过分子细胞实验研究突变对ADGRG2和CFTR及下游通路功能的影响；通过定点突变及基因敲除小鼠，检测变异对小鼠生殖道组织形态和生殖功能的影响和机理，从而明确目前发现的人类突变的致病性及其分子遗传机制。本课题研究成果将为进一步理解CBAVD发生机制提供线索和依据。

先天性双侧输精管缺如（CBAVD）是导致梗阻性无精症和男性不育的重要原因之一，CFTR基因突变是其主要致病基因。近期研究发现ADGRG2突变也可导致CBAVD，课题组前期在中国人群中首次报道了ADGRG2新突变。本研究通过CRISPR/Cas9构建了Adgrg2 p.C559Y（人类ADGRG2 p.C570Y同源位置）突变小鼠，明确突变对CBAVD发生的影响。进一步构建ADGRG2敲除细胞系并进行RNA-seq，发现差异表达基因富集在细胞表面受体信号、转运调控和细胞通讯等途径。本研究揭示了ADRGR2突变导致CBAVD的可能机制。