Using cytochrome β (Cyt β) gene for species identification of dog, cat, and tiger to ensure food authenticity and drugs

Abstract

Adulteration food products from animal still happen until now. Species identification method development in food and medicine derived from animal was needed to prevent falsification information. Molecular genetic improvement allows the detection is carried out at the level of DNA, so the results more accurate, although processed. Research on several meat have been conducted by several researchers using DNA mitochondrial DNA (mtDNA). Using mtDNA because it has high copy number in a cell, compared with nuclear DNA. In this case where the amount of extracted DNA is very small or degraded. Gene used as marker specific species is cytochrome β (cyt β) because it has varied sequences. The objective of this research was to study species authentication (i.e. dog, cat, and tiger) to ensure animal origin in product using cyt β gene specific marker. Total DNA samples for each species which identified are three samples were consisting blood (cat), cooked meat (dog), feces (tiger), and as a comparison used blood sample from several animal (i.e. goat, chicken, cattle, sheep, horse, rat) and pork. Reverse primer specific for dog, cat, and tiger was designed using MEGA 5 software. DNA extraction and fragment amplification was conducted using phenol-chloroform and multiplex PCR method, respectively. Multiplex PCR is a variant of PCR which many primers were used together for amplification of multiple region. This research showed that different length of amplification for the species tested (dog, cat, and tiger) were 523, 331, 319 bp, respectively; and for the comparison species (goat, chicken, cattle, sheep, pig, horse, and rat) were 157, 227, 274, 331, 398, 439, and 603 bp, respectively. Species specificity also indicated by high reverse primer homology percentage. Specific fragment amplification on genome pool with closed fragment length should be separate to avoid band overlapped between species. Taxonomy hierarchy (i.e. dog, cat, and tiger) could be distinguished to the species level.