Sex identification of individuals is an important task in wildlife forensics as well as in conservation biology. It helps scientists understand population sex ratios with respect to maintaining genetic diversity, managing inbreeding depression and preventing the demographic consequences of sex-biased poaching. The literature on the use of mammalian molecular sex markers indicates that the success of accurate sex identification is variable across species. Very little is known about the effectiveness of such markers on the mammals of South and Southeast Asia. Therefore, we selected and tested three sets of universal primers for low-cost gel-based sex identification of mammals. We amplified different sets of markers-SRY (157 bp) and 12S rRNA (384 bp); Y-53-SRY (225 bp) and ZFX/ZFY (P1/P2; 445); SRY (157 bp) and 12S rRNA (151 bp)-to be used with different types (tissue, hair and skin) of samples from 20 mammalian species. All three sets of primers amplified the sex-specific fragment in a range of samples from hair to tissue. With an increasing number of field studies using non-invasively collected samples, this proposed low-cost gel- based method of molecular sexing may be applied in various aspects of the ecology and biology of South and Southeast Asian mammals, their conservation and forensics. We suggest that at least two sets of primers be used for any biological samples to avoid ambiguity.
Keywords: Duplex PCR; Internal marker; Mitochondrial DNA; Sex identification; Wildlife forensic science.