Molecular sex diagnosis in castoridae

Beavers do not exhibit any external sexual trait. Therefore, a simple method was established to differentiate between males and females by verifying the male-specific SRY gene. Genomic DNA was prepared from hair root cells. Male samples displayed an electrophoretic 157-bp band derived from the SRY gene after polymerase chain reaction (PCR) amplification. This band is missing in female samples. A 375-bp fragment of the mitochondrial cytochrome b gene served as internal control and was visible in all samples. The technique can easily be used as a standard monitoring method, and is noninvasive, quick, and reliable. Zoo Biol 21:305–308, 2002. © 2002 Wiley-Liss, Inc.