What is a major potential problem with dna evidence? having too much dna contamination from other sources having to heat up dna to keep it from degrading having too many matches to dna typing

Contamination from other sources

Explanation:

DNA as an evidence can be extracted from biological materials obtained from the scene of crime or from the requested samples from victim or culprit. The biological materials include blood, hair, bones, nails, vaginal swab, sweat, seminal fluids and other possible sources. These samples should be collected and preserved with utmost care so that contaminants like dust, microbes, cannot damage the integrity of the evidence.

Also the mixing of two biological fluids should be avoided.  If contaminants are administered in the evidence can produce error in extraction as well as examination of the DNA evidence. Therefore, clean instruments should be used for collection like droppers, vials and plastic bottles.