Forensic DNA: Y-Chromosome

The Y chromosome DNA testing enables examination of the male-specific portion of biological evidence. This capability can be especially important in situations where a small amount of male DNA may be recovered in the presence of excess female DNA, such as in sexual assault evidence. Y chromosome analysis can also benefit missing persons investigations as it extends the range of potential reference samples. Since fathers pass their Y chromosome onto their sons unchanged (except for an occasional mutation), all males in a paternal lineage will possess a common Y chromosome haplotype.

A core set of Y chromosome short tandem repeat (Y-STR) loci have been selected for use in human identification applications. The core Y-STR loci were recommended by the SWGDAM Y chromosome subcommittee in 2003 and include the following: DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS438, DYS439, and the multi-copy locus DYS385 a/b. Commercial kits now exist that can co-amplify all of the core Y-STR loci in a single multiplex reaction. Several groups are also exploring additional Y-STR loci that have the potential to improve the power of discrimination for Y-STR testing.

View a list of NIJ-funded research projects.

Date Modified: October 11, 2012