Yen P H, Chai N N, Salido E C
Division of Medical Genetics, Harbor-UCLA Medical Center, Torrance 90502-2064, USA.
Hum Mol Genet. 1996 Dec;5(12):2013-7. doi: 10.1093/hmg/5.12.2013.
The DAZ (Deleted in AZoospermia) and DAZLA (DAZ-like autosomal) genes may be determinants of male infertility. The DAZ gene on the long arm of the human Y chromosome is a strong candidate for the 'azoospermia factor' (AZF). Its role in spermatogenesis is supported by its exclusive expression in testis, its deletion in a high percentage of males with azoospermia or severe oligospermia, and its homology with a Drosophila male infertility gene boule. No DAZ homologous sequences have been found on the mouse Y chromosome. Instead, a Dazla gene was isolated from mouse chromosome 17 and has been considered to be a murine homologue of DAZ. However, the homology between human DAZ and mouse Dazla is not strong, and Dazla contains only one of the seven DAZ repeats found in DAZ. We report the isolation of the human DAZLA gene by screening a human testis cDNA library with a DAZ cDNA clone. DAZLA encodes only one DAZ repeat and shares high homology with the mouse Dazla, indicating that these two genes are homologues. Using a panel of rodent-human somatic cell lines and fluorescence in situ hybridization, the DAZLA gene was mapped to 3p24, a region not known to share homology with mouse chromosome 17. The DAZLA gene may be involved in some familial cases of autosomal recessive male infertility.
无精子症缺失基因（DAZ）和类DAZ常染色体基因（DAZLA）可能是男性不育的决定因素。人类Y染色体长臂上的DAZ基因是“无精子症因子”（AZF）的有力候选基因。它在精子发生中的作用得到了以下几点支持：它仅在睾丸中表达，在高比例的无精子症或严重少精子症男性中缺失，以及与果蝇雄性不育基因boule具有同源性。在小鼠Y染色体上未发现DAZ同源序列。相反，从小鼠17号染色体上分离出了Dazla基因，并被认为是DAZ的小鼠同源物。然而，人类DAZ与小鼠Dazla之间的同源性不强，并且Dazla仅包含DAZ中发现的七个DAZ重复序列之一。我们报告了通过用DAZ cDNA克隆筛选人类睾丸cDNA文库来分离人类DAZLA基因的过程。DAZLA仅编码一个DAZ重复序列，并且与小鼠Dazla具有高度同源性，表明这两个基因是同源物。利用一组啮齿动物 - 人类体细胞系和荧光原位杂交技术，将DAZLA基因定位于3p24，该区域与小鼠17号染色体没有同源性。DAZLA基因可能与某些常染色体隐性男性不育的家族病例有关。
