A DE-NOVO MUTATION IN HUMAN SRY GENE - CODON 113-GCA -] ACA FOUND IN AN XY FEMALE

The recent advances in sex determination of eutherian mammals (includi ng humans) have disclosed a gene on the short arm of the Y chromosome which initiates male development, termed SRY (sex-determining region o f the Y) [1 - 3]. It is a highly conserved single copy gene with 250 b p of core sequence, encoding a protein sequence with an 80 residue str etch, which is characteristic of a DNA-binding motif known as the HMG box (high mobility group box)[4]. This great achievement in life scien ce gives the insights into the studies of molecular biology on sex det ermination. We herein describe a new de novo mutation in the SRY gene of an XY female. The result suggests that mutations in the SRY motif p lay an important genetic role in human sex reversal syndrome.