Cytochrome b and HVI sequences of mitochondrial DNA to identify domestic animal hair in forensic casework

Biological traces that appear at the scene of a crime or on the body of the victim may be of human, animal and/or vegetable origin. Among those of animal origin, household pets are a common source, with pet hair being one of the most frequent traces found. Consequently, it is necessary to have laboratory methods capable of identifying traces from pets and domesticated animals in general. Savolainen et al. [1] have developed a basic method of sequencing the HVI region of mitochondrial DNA from Canis familiaris using single hairs as template, with a discrimination capacity of 1 in 10 individuals. The species from which a biological trace has come can be identified by analyzing a short fragment of the cytochrome b (cytb) gene sequence of the mitochondrial genome. This gene contains species-specific information and has been used in phylogenetic as well as in forensic investigations in a number of studies. Parson et al. [2] have confirmed the usefulness of cytb analysis in identifying the biological origin of casework specimens.