In the forensic science, genetic species identification based on DNA sequence differences and similarities will be used for crime survey. The mtDNA is much expanded for using as a marker in species and individual identification. Cytochrome C oxidase subunit I is a part of mtDNA with 1548 base pair length. There are three different subunits of cytochrome C oxidase, COI, COII and COIII. Between the three mitochondrial genes which are coding the cytochrome C oxidase subunits, COI is the largest and the most conserved between them. This is the first study on the COI gene here in Malaysia. Cytochrome C oxidase subunit I (COI) was studied to check the COI gene polymorphism in Malay population and investigation the usefulness of this gene as forensic marker. For this aim, the blood samples were collected from Malay people from different states. The PCR was done by using of extracted DNA from the blood and the COI gene was amplified with specific designated primers. Therefore, the desired region was revealed in the gel electrophoresis. The 13 nucleotide variations were observed within 1548 bp after sequencing of the samples and comparing with Anderson reference sequence
