Genetic Studies of Male Infertility

Abstract

Infertility is the inability of a sexually active, non-contraception couple to achieve pregnancy in one year. Generally, infertility is classified as either primary (67-71%) when no pregnancy has ever occurred or secondary (29-33%) where there has been a pregnancy, regardless of the outcome. It affects 13-18% of couples of reproductive age worldwide and is treatable in many cases [1]. Although, infertility is not life threatening, it is psychologically a traumatic condition associated with social stigma in certain societies resulting in intense social and parental pressure to attain biological parenthood; hence many infertile couples choose to undergo assisted reproductive technology as a form of treatment. In recent years, it has been demonstrated that up to 50% of infertility cases are associated with male factor because of spermatogenic failure; interestingly in which ~70% of the underlying etiological cause(s) are known but remaining 30% are referred to as idiopathic infertility [2] Thus, the etiology of male infertility is complex and can be reflected in a variety of conditions like defective spermatogenesis, congenital absence of bilateral vas deferens (CABVD), infections, and immunological disorders such as antisperm-antibodies, diabetes, obesity, pituitary disorders, and imbalance in levels of gonadotrophic hormones. Genetic factors are considered to be significant in male infertility [3]. Hence, the aim of the study is to investigate the chromosomal aberrations, azoospermia factor (AZF), cystic fibrosis transmembrane regulator (CFTR) gene mutations in the peripheral blood lymphocytes (PBL) of infertile men with abnormal sperm parameter and compare it with healthy fertile control subjects to delineate the genetic causes of male infertility. This thesis comprises of six chapters. The first chapter summarizes about male factor infertility: incidence, classification, etiology, genetic factors, and treatment options. In around 50% of infertile couples, male-related causes are involved, such as impaired sperma