Popis: |
Recent advances in the knowledge of sexual development have been obtained by studying individuals with dysgenetic gonads and reproductive tract alterations. By using probes Y-ADN in these patients, it was found that a gene of the short arms of Y chromosome, induces testicular differentiation. The way this gene acts is not known, but the observation that there are homologue sequencies in X and Y, suggests the possibility that sexual differentiation depends on genic doses. Other genes like the one that codifies for antigen H-Y, for skeletal maturation, body growth, dental size and spermatogenesis regulation, have been identified in chromosome Y. Findings that have allowed a better understanding of genetic and cytogenetic factor involved in sterility-infertility. |