Table 2.

A summary of advantages and disadvantages of nuclear and mitochondrial DNA in muscle food origin identification.

DNA	Advantages	Disadvantages
Nuclear	Sequence information is conserved and stable [62].	More susceptible to fragmentation in extensive food processing than mitochondrial DNA [70].
	Diploidy (suitable for genotyping) [68].
	Multiplex species identification at multiple target sites [68].
	Enable accurate quantification of meat weight based on the DNA copy number [69].
	Contains repetitive sequences (e.g., short interspersed nuclear elements (SINE) and long interspersed nuclear elements (LINE)) which can serve as amplification products, lowering the limit of detection [67].
Mitochondrial	High copy number per cell (≈2500 copies) and varies in different tissues [71,72].	Subject to mutation at primer binding region [72].
	Higher probability of obtaining positive results in fragmented DNA caused by intense food processing [73].
	Relatively higher in mutation rate than nuclear genes (suitable to discriminating closely related species, e.g., chicken vs turkey) [70].	Quantification of meat by transforming copy numbers to the weight proportion of meat is challenging [72].
	More resistant to fragmentation by heat compared to nuclear DNA [70].