All vertebrates become either males or females. However, the details of how the system that gives rise to males and females evolved has been poorly understood. In order to better understand this system it has been necessary to study a large number of various sex-determination systems. NIBB Research Fellow Shuhei Nakamura and Associate Professor Minoru Tanaka of NIBB’s Laboratory of Molecular Genetics for Reproduction have focused on the gene sox9, which plays an essential role in the sex-determination system in mammals, and performed functional analysis using medaka. The results of this research show that unlike in mammals medaka-sox9 is not involved in testis-determination. This shows that the very system by which sex is regulated has arisen afresh through the evolutionary process. These results were published in the comprehensive scientific journal PloS ONE.
For details please the journal article here.