U.S. flag

An official website of the United States government, Department of Justice.

Automated DNA Typing: The Method of the Future?

NCJ Number
164311
Author(s)
H. A. Hammond, C. T. Caskey
Date Published
January 1996
Length
15 pages
Annotation
DNA typing has had a significant impact on crime fighting methods over the past decade, and the primary DNA typing method used in the United States involves southern blotting analysis of restriction fragment length polymorphism-variable number of tandem repeat (RFLP-VNTR) genetic loci.
Abstract
The RFLP-VNTR method has proven to be highly discriminatory and reliable, although it has limitations that do not make it the ideal method for forensic typing. For example, the method is time-consuming, requiring weeks to months to finish a case, and this is not sufficiently rapid for investigative purposes. The method also requires the extraction of large amounts of high- quality DNA from evidence samples and is therefore not useful in cases where DNA has been degraded. A molecular biological technique is suggested based on the polymerase chain reaction (PCR). The PCR method makes copies of a section of DNA extracted from an evidence or known sample, and any portion of DNA can be amplified if the specific nucleotide sequence of DNA near or through the region is known. At the Baylor College of Medicine in Houston, 13 so-called short tandem repeat loci are being studied using a computerized PCR technique. Acceptance of the technique by the laboratory community, however, is several years away. 13 references and 2 figures

Date Published: January 1, 1996