NCJ Number
127674
Date Published
1990
Length
7 pages
Annotation
Although DNA profiling has become associated with a method based on the technique of "Southern" blotting, this procedure does have some limitations in its ability to identify individual genetic variation for forensic purposes. New techniques based on the polymerase chain reaction (PCR) procedure will probably develop into the preferred method of analysis in forensic sciences.
Abstract
The "Southern" blot procedure is limited by its requirements of relatively large and undegraded samples of DNA tissue. This technical paper discusses the PCR approach to identifying genetic variation which meets two requirements: the appropriate choice of highly variable regions of DNA for amplification and the development of efficient methods for detecting variation in the amplified product. The PCR technique cannot use the minisatellites used as hybridization probes in the "Southern" blot method; instead, either the HLA or Major Histocompatability genes can be utilized. Knowledge of the sequences of HLA variants makes possible the use of three assay options: dot-blot hybridizations, digestion at sequence-specific restriction sites, and direct sequencing. The data obtained through any of these methods can be interpreted within the context of existing HLA nomenclature and can be compared to data obtained through either of the other two methods.