Application of Mitochondrial DNA for Cytochrome b Gene to Species Identification in Forensic Science

Abstract

The variation of mitochondrial cytochrome b gene(cyt b) has been a rich source of phylogenetic inference in a wide range of animal species. In the present study, PCR-RFLP pattern of cyt b were compared to identify species of animals for forensic science investigation. Using total DNA isolated from blood of five human individuals, eight species of mammal(baboon, cow, pig, dog, cat, bear, deer and raccoon dog) and two species of bird(chicken and wild duck), cyt b were analyzed by using the PCR method. Using the primers designed for cyt b by Chikuni et al. (1994), cyt b was amplified to obtain about 700bp fragment from seven mammals(human, baboon, cow, pig, cat, bear and deer) and two birds (chicken and wild duck). The PCR products were digested with two restriction endonucleases(Hae III or Hinf I), and the difference was observed among mammals and birds as PCR-restriction fragment length polymorphism (RFLP). PCR-PFLP patterns with Hinf I of human differed from other animals.   In this study, nine animal species could be simply identified by this method. DNAs from some spiecies were not able to be amplified probably depending on a mismatch of primers. The polymorphism in cyt b was a useful tool for species identification in a forensic casework. Further study is needed to apply this method to a forensic casework.