Target of DNA Analysis Definition Major Limitations of Analysis
Short Tandem Repeats Short sequences of DNA that contains short segments consisting of 2-7repeating base pairs •  Unsuitable for the analysis of highly degraded or low copy number DNA samples
•  Inconsistency of number of STR markers in different DNA databases
Single Nucleotide Polymorphism DNA sequence variations that occur when a single nucleotide (A, T, C, or G) in the genome sequence is altered. •  Less informative per locus than STR
•  Unsuitable for DNA mixtures
Low Copy Number or Low-Template DNA Less than 200 picogram of DNA found in a sample •  Ease of contamination and amplification of contaminants
•  Mixed profiles being produced and wrongful accusations
Mitochondrial DNA A circular molecule of DNA 16,569 base pairs in size,  obtained from the mitochondrion organelle found within cells •  Less discriminatory (maternal inheritance)
•  Relatively time consuming and expensive
DNA Methylation DNA methylation is a biochemical process involving the addition of a methyl group to the cytosine or adenine DNA nucleotides •  Large amount of samples needed
•  Labor-intensive and time-consuming
Table 1: Definition of DNA analysis targets and major limitations.