Forensic biology is the scientific analysis of biological evidence to provide objective information on legal matters or those that pertain to criminal and civil law. Biological evidence such as bodily fluids or tissues that may be found at crime scenes can be analyzed through deoxyribonucleic acid (DNA) typing. Typing requires detection and screening of the biological evidence, such as blood, semen, or saliva, extracting the DNA from a specimen, amplifying specific regions of the DNA using the polymerase chain reaction (PCR), and typing the resulting PCR products to determine a DNA profile. The DNA profile from the evidence is then compared to known profiles from suspects, victims, or database samples to determine the significance of the result. Samples containing mixtures require additional interpretation to infer individual donor allele designations. Forensic biologists must also assess the statistical significance of their results, write reports, and testify in court.