Question

Give three instances demonstrating how genes regulate sex determination in mammals. Please provide all citations.

Answer 1

Genes regulate sex determination in mammals, in males XY genes are present while in female XX genes are present. Means presence of y chromosome indicate the presence of maleness. Genes for gonads development are responsible for sex determination, development into ovaries determines the femaleness and development of testicles determines the femaleness. In mice SRY's primary determines the male development. It develops gonads in males but not females. The SRY protein also  regulate the transcription of other genes.  SOX9 gene, induce  male differentiation and develop in  male gonad immediately after SRY is first expressed. DAX1 gene disrupts SRY function   prevent induction of the male gonads. In Drosophila, XX represent the femaleness and XO represent maleness.