The Y chromosome and primary sexual differentiation
R. Bernstein
The mammalian Y chromosome plays a dominant role in initiating fetal
testicular differentiation. Testicular differentiating genes on the Y
chromosome can be serologically detected as H-Y antigen. The correlation of
numerical and structural abnormalities of the X and Y chromosomes, combined
with H-Y antigen reactivity, gonadal histology, and phenotype, has
contributed to mapping the locus of these genes on the Y chromosome and has
elucidated some of the mechanisms responsible for anomalous primary sexual
differentiation. The causes for failure of gonadal differentiation despite
the presence of a Y chromosome or for testicular differentiation in the
absence of a detectable Y are discussed. Evidence is presented for genes on
the X chromosome that regulate the activity of testicular differentiating
genes on the Y chromosome.