Compound genetic factors as a cause of male infertility

A 40 year old healthy Chinese male with primary infertility was seen in a university male infertility and genetic counselling clinic. He presented with congenital bilateral absence of the vas deferens (CBAVD) and the finding of testis atrophy. Fine needle aspiration mapping of the testis identified and localized sperm production within the testicles for in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Careful evaluation of testicular cytology revealed late maturation arrest of spermatogenesis, Cystic fibrosis gene mutation analysis revealed heterozygosity for the 5T variant within the polypyrimidine tract of intron 8. Cytogenetic analysis revealed a pericentric inversion of chromosome 6 with break points at p12 and q21 [46,XY,inv(6)(p12q21)]. This case illustrates that spermatogenesis is not necessarily normal,with congenital bilateral absence of the vas deferens. Compound genetic defects may coexist and underlie male infertility.