Abstract
Forensic haplotype analysis of the male Y chromosome is currently used to establish the number of male donors in sexual assaults, the number of male bleeders in blood pattern analysis, and for ancestry correlation to genetic founder populations in biogeographic studies. In forensic laboratory applications, its primary use is for DNA profile generation with trace amounts of male DNA in the presence of excess female DNA (e.g. spermatozoa identification, male component of fingernail scrapings). Our study supports the potential use of the Y chromosome in a "dragnet" approach (most haplotypes are unique) similar to that described by Kayser in 2017 for solving a cold case sex assault and homicide in The Netherlands. Our study also researched the potential for the identification of an ancestral Irish genetic "footprint" linked to surname O'Brien and identified multiple founder group origins in Ireland and England as well as three samples with the Dal Riata (a Gaelic overkingdom) ancestral haplotype. This study indicates correlation to ancestral Irish ancestry by haplotype but not conclusively to the O'Brien surname.