This indicates that a fully differentiated mammalian nucleus is able to direct the entire developmental process. No information is lost during development. Many organisms determine the gender of a developing individual based on the genotype at sex chromosomes. In normal individuals, XX specifies female development, and XY specifies male development. However, aneuploid individuals develop differently in Drosophila and mammals, due to differences in the underlying genes that are controlling these developmental processes.
Hormone masculinizes other tissues.
The full SXL polypeptide in present in females, absent in males, and this difference is the primary signal used in sex specific differentiation in somatic tissues. Alternate splicing of the dsx pre-mRNA occurs in males where TRA is absent. The alternative products of the dsx gene control sex-specific phenotypes. The following is a summary of the genetic cascade in Drosophila. This occurs early in gestation.