CAG repeats polymorphism of androgen receptor gene, Kennedy’s disease and male infertility

Genetic factors are a common cause of severe pathozoospermia and male infertility. An increase in the length of trinucleotide repeats causes a number of progressive neurodegenerative diseases, including spinal bulbar muscular atrophy — Kennedy syndrome. This neuromuscular disease is caused by the CAG repeats expansion in the androgen receptor gene (AR) and is characterized by endocrine disorders, testicular atrophy, hypogonadism, gynecomastia, and infertility due to azoospermia or oligozoospermia. Variation in the number of CAG repeats of the AR gene may be associated with impaired spermatogenesis and male fertility. The article presents current information about the androgen receptor gene, protein encoded by it and its function, Kennedy syndrome and the effect of the number of AR gene CAG repeats on the male reproductive system and fertility