Cafuk, T.: Mediterranean monk seal (Monachus monachus) sex determination by polymerase chain reaction. Diploma Thesis. Faculty of Veterinary Medicine. Zagreb, 2011



The Mediterranean monk seal (Monachus monachus) is the only seal species that inhabits Mediterranean Sea and one of the most endangered animal species of the world. Once found throughout Croatian part of the Adriatic Sea, the Mediterranean monk seal is considered extinct since 1992, although some individuals from the neighbouring populations enter the Adriatic Sea and stay there temporarily. Conservation of a population in a certain habitat relies strongly on the understanding of the population structure. Any kind of data considering the highly endangered Mediterranean monk seal contributes to a better understanding of the species biology. In this study polymerase chain reaction (PCR) has been applied to identify sex from the bone tissue samples. Genome DNA has been extracted from 2 museum monk seal skulls and one from a phalanx. Six other mammals of different species and of known sex have been used as control samples. With the four oligonucleotide primers, used in the PCR, fragments (445 bp and 224 bp) of different length have been obtained. Primers were used to simultaneously amplify a part of the sry gene located on the Y chromosome wich exists only in males, and control regions of ZFX/ZFY, which exist in males and females. The sex of 2 monk seal samples has been successfully determined, while sex determination of one sample failed.