Genetics of Male Infertility

Infertility is defined as the state in which a couple wanting a child is unable to conceive after 12 months of regular intercourse in the absence of contraceptives. It is a problem faced by couples rather than individuals.

Global incidence of infertility is about 13-18%. Male infertility is found to have a role in approximately 50% of infertile couples.

In India, although population growth is a major concern, there are a substantial number of infertile couples. Thus infertility is considered as an important national problem concerning reproductive health.

Recent advances in assisted reproductive technologies (ART) make it possible for many infertile men with severe male factor infertility to father children. However a significant proportion of infertile males with azoospermia and severe oligozoospermia have a genetic etiology for reproductive failure. Thus these technologies raise concerns about passing on genetic abnormalities to the offspring of these men. Thus, it is important for the clinicians involved in the treatment of these couples to initiate genetic evaluation and counseling prior to any assisted reproductive procedure.

The three most common genetic factors related to male infertility are cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations leading to congenital absence of the vas deferens (CAVD), chromosomal (karyotype) abnormalities and Y-chromosome microdeltions in the azoospermia factor (AZF)locus.

Infertility can be associated with other far less common genetic conditions. Examples include Kennedy's disease, Kallman's syndrome, Prader Willi syndrome, Myotonic dystrophy and Kartagener's syndrome.