question: Which is the main abnormality that arises with Sox9 locus duplication?
answer: The 46,XX testicular disorder of sex development (DSD), also known as 46,XX male syndrome, is a rare form of DSD and clinical phenotype shows complete sex reversal from female to male. A complex network of genes determines sex in mammals. Differentiation of testicular tissue in 46,XX individuals is seen either in XX males, the majority of them with SRY gene, or in individuals, usually SRY(-), with ovotesticular disorder of sex development (OT-DSD). SOX9 is one of the genes that play critical roles in male sexual differentiation.