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Polymerase Chain Reaction (PCR) Method for Sex and Species Determination with Novel Controls for Deoxyribonucleic Acid (DNA) Template Length

NCJ Number
Date Published
January 1992
15 pages
Human X and Y chromosome alpha-satellite sequences lying within higher order repeats were amplified by the polymerase chain reaction (PCR) in genomic deoxyribonucleic acid (DNA) isolated from blood, bone, and several other tissues and specimens of potential forensic science interest.
DNA was isolated from blood cells, bloodstains, hair roots, buccal cells, sperm-containing postcoital vaginal swabs, and bone tissue by the proteinase K digestion and phenol-chloroform extraction methods. DNA quantity and quality were assessed by ultraviolet visualization of ethidium-bromide-stained agarose minigels following submarine electrophoresis. DNA quantity was also estimated by a spectrophotofluorometric method. Testing was carried out using PCR protocols that employed Thermophilus aquaticus and Thermus flavis thermostable DNA polymerases. It was found that X and Y sequences could be coamplified under some of the PCR conditions employed. Monomorphic sequences in the 3'-apolipoprotein B gene (designated H) and in an alpha-satellite higher order repeat on Chromosome 17 (p17H8, D17Z1) were likewise amplified in the specimens. Amplification of the X, H, and D17Z1 sequences were primate-specific among the common animals tested and thus provided species of origin information about a specimen. It was also determined that X and Y sequence amplification can provide information about the sex of origin. The authors suggest that amplification of X and D17Z1 or H sequences may provide "relaxed" and "stringent" controls for appropriate PCR amplification tests on forensic science specimens. 40 references and 9 figures (Author abstract modified)

Date Published: January 1, 1992