Rajender Singh, Rajani Vutukuri, Gupta Nalini J, Chakravarty Baidyanath, Singh Lalji, Thangaraj Kumarasamy
Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India.
J Androl. 2006 Nov-Dec;27(6):785-9. doi: 10.2164/jandrol.106.000166. Epub 2006 Jun 28.
Androgens, acting through the androgen receptor (AR), play a role in secondary sexual differentiation from the prenatal stage to adulthood, including spermatogenesis. The AR gene has 2 polymorphic trinucleotide repeats (CAG and GGN) in exon 1. The CAG repeat length polymorphism has been well studied in a variety of medical conditions, including male infertility. Many of these studies have shown an association of the expanded CAG repeats with male infertility, although this is not true for all populations. The GGN repeat, in contrast, has been less thoroughly studied. Thus far, only 4 reports worldwide have analyzed the GGN repeat, alone or in combination with the CAG repeat, in male infertility cases. No such study has been undertaken on infertile Indian men. Therefore, we have analyzed AR-GGN repeats in a total of 595 Indian males, including 277 azoospemric, 97 oligozoospermic, and 21 oligoteratozoospermic cases, along with 200 normozoospermic controls. The analysis revealed no difference in the mean number or the range of the repeat between cases (mean = 21.51 repeats, range 15-26 repeats) and controls (mean 21.58 repeats, range 15-26 repeats). Furthermore, no difference was observed when azoospermic (mean = 21.53 repeats, range 15-26 repeats), oligozoospermic (mean = 21.46 repeats, range 15-26 repeats), and oligoteratozoospermic cases (mean = 21.48, range 19-26 repeats) were compared individually with the controls.
雄激素通过雄激素受体(AR)发挥作用,在从产前阶段到成年期的第二性征分化中起作用,包括精子发生。AR基因在第1外显子中有2个多态性三核苷酸重复序列(CAG和GGN)。CAG重复长度多态性在包括男性不育症在内的多种医学病症中已得到充分研究。许多这些研究表明,CAG重复序列扩展与男性不育症有关,尽管并非所有人群都是如此。相比之下,GGN重复序列的研究则不够深入。到目前为止,全球仅有4篇报告分析了男性不育症病例中的GGN重复序列,单独分析或与CAG重复序列联合分析。尚未对印度不育男性进行此类研究。因此,我们分析了总共595名印度男性的AR-GGN重复序列,包括277例无精子症患者、97例少精子症患者和21例少弱精子症患者,以及200例正常精子症对照。分析显示,病例组(平均=21.51次重复,范围15-26次重复)和对照组(平均21.58次重复,范围15-26次重复)之间的重复序列平均数或范围没有差异。此外,当分别将无精子症患者(平均=21.53次重复,范围15-26次重复)、少精子症患者(平均=21.46次重复,范围15-26次重复)和少弱精子症患者(平均=21.48,范围19-26次重复)与对照组进行比较时,未观察到差异。