Genes and gene defects affecting gonadal development and sex determination

Abstract

Sex in mammals is determined genetically with the acquisition of either the XX (female) or XY (male) chromosomes at the time of fertilization. The chromosomal sex will determine if, during embryogenesis, ovaries or testes form from the bipotential gonadal anlage, the genital ridges. Hormones produced by testes and ovaries will then drive most, if not all, secondary sexual characteristics, resulting in the female or male phenotype. Each of these sequential steps is promoted by specific genes and mutations in these genes can lead to variants of sex development (VSDs), also called differences of sex development (DSDs).