These species that rely upon temperature for their sex determination do not have the SRY gene, but have other genes such as DAX1, DMRT1, and SOX9 that are expressed or not expressed depending on the temperature.
As especies que determinan o sexo coa temperatura non teñen xene SRY, pero teñen outros xenes como o DAX1, DMRT1, e SOX9 que se expresan ou non dependendo da temperatura.