NCJ Number
139772
Journal
Journal of Forensic Sciences Volume: 37 Issue: 6 Dated: (November 1992) Pages: 1640-1651
Date Published
1992
Length
12 pages
Annotation
This article reports on an investigation of the relationship between the frequencies of restriction fragment length patterns (RFLP's) in DNA typing calculated by various methods as well as how the number of individuals collected in the reference database may affect that frequency; it also demonstrates that regardless of the method chosen, the frequency of occurrence of a pattern is rare.
Abstract
In recent years the application of DNA typing information to criminal investigations has gained widespread acceptance. The primary method currently used relies on DNA RFLP variation between individuals. These variations are identified by using variable number tandem repeat DNA probes. As this technology becomes more widely used, it is crucial that scientifically valid methods of interpreting the significance of a DNA typing result be adopted. The method chosen should not only give a reliable approximation of the statistical likelihood of a particular RFLP's occurring, but should also be easy to present and to be understood by the court. This article describes five methods for the calculation of a frequency of occurrence of a RFLP (fixed bin genotype, floating bin phenotype, floating bin genotype, National Research Council method of using fixed bins, and the National Research Council method of using floating bins). The calculations discussed indicate that the fixed bin genotype method produces a frequency similar to that obtained from floating bin phenotypes. Additionally, regardless of the method chosen the database size, the frequency of any particular banding pattern in the population over several loci was found to be rare. 9 figures, 2 tables, and 11 references