Molecular Analysis of Infertility

The existence of a gene or a gene complex, associated with normal spermatogenesis was first postulated on the basis of a cytogenetic analysis that showed macroscopic deletion of the distal part of the Y chromosome in men with azoospermia. This gene or gene cluster was defined as azoospermic factor (AZF). Subsequent PCR- based screening studies used to amplify sequence tagged sites (STS) spanning the Y chromosome, facilitated the detection of small interstitial deletions (microdeletions) of Yq11 in azoospermic and severely oligospermic men. Polycystic ovary syndrome (PCOS) is associated with chronic anovulation, hyper androgenemia, insulin resistance/hyperinsulinemia and high incidence of obesity. Leptin, product of ob gene is an adiposite secreted molecule that signals magnitude of energy stores to the brain and has been recently shown to have important effects on the reproductive axis of rodents. Follistatin plays an important role in female physiology by regulating FSH levels by blocking activin levels. Failure to regulate FSH has been implicated to be a potential cause of premature ovarian failure. Familial PCOS has been proposed to be linked to a site near follistatin gene.