Genetic causes of male infertility.

Male infertility has often been ascribed to infections, immunologic factors, chemical insults or malformations. About 10% of infertile males have severe defects in sperm production. Lately, research has focused on possible genetic aetiologies. In this review genetic causes of male infertility are discussed. For pragmatic reasons three groups have been defined. In the first group, disorders of sexual differentiation associated with male infertility are considered. In the second group, male infertility is discussed in a context of some genetic diseases. In the third group, genetic causes for isolated defects of sperm production and function are reported.