| 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
|
