A locus (plural- loci), refers to a particular location on a gene. Analysts examine DNA in sections, taking just small parts of the chromosome and examining the functional genes on them thereof. The human body contains something around 70,000 genes, however, the exact number is unknown. Analyzing DNA is a complex process and involves amplification and often also producing copies of the DNA.
When one chooses to do a DNA test, the laboratory they choose will analyze a fixed number of markers and compare these markers to determine if there is a possible biological relationship between the two people. laboratories with ISO 17025 accreditation will take a number of loci as subject of examination, though other laboratories may take less as this makes the process quicker and cheaper, although less reliable. Paternity DNA tests rely on comparing the loci between the child’s DNA and the father’s DNA. Paternity will be an inclusion if the loci on the alleged father’s DNA are identical as those on the child’s genetic profile.