NCJ Number
223112
Journal
Forensic Science International: Genetics Volume: 2 Issue: 3 Dated: June 2008 Pages: 219-225
Date Published
June 2008
Length
7 pages
Annotation
This paper considers identification problems based on DNA marker data when there is DNA available from two persons and there is uncertainty about the relationship between the two individuals and a number of hypotheses that describe the possible relationship are available.
Abstract
The task is to determine the most likely family relationship between the two persons. Although this task is fairly standard, there are some problems that cannot be solved by using DNA from independently segregating loci; for example, the likelihoods for a grandparent-grandchild, uncle-niece, and half-siblings coincide for such DNA data, which makes it impossible to distinguish these relationships based on markers normally used for forensic identification problems. Generally, the issue can be resolved by using linked autosomal markers. This paper presents an explicit formula for a pair of linked markers. The formula extends to independent pairs of linked markers. Although this approach contributed to an understanding of the problem, more markers were required. The Lander-Green algorithm was applied to obtain needed results. Simulation experiments are presented based on a range of scenarios. Useful results can be obtained using available freeware (MERLIN and R). Although linked autosomal markers constitute the main focus of the discussion, some alternative or supplementary approaches based on mtDNA, sex chromosomes, and prior information are mentioned. 3 tables, 4 figures, and 25 references