Implementing a biogeographic ancestry inference service for forensic casework.

The Centre of Forensic Sciences has validated the Precision ID Ancestry Panel on the Ion S5™ Massively Parallel Sequencing instrument for use in forensic casework. The focus of this paper is the development of reporting guidelines for implementation of the biogeographic ancestry inference service based on the Admixture Prediction results produced using the Torrent Suite™ Software (Thermo Fisher Scientific). The Admixture Prediction algorithm estimates the genetic ancestry of a sample using seven root populations (Europe, East Asia, Oceania, America, Africa, South Asia, and Southwest Asia). For individuals that declared a single ancestry, there was a high correlation between the declared ancestry and the ancestry predicted by the algorithm. However, some individuals with declared ancestries of Southern Europe, Southwest Asia, South Asia and Horn of Africa had Admixture Predictions that were composed of two or more root populations at 20% or greater. For individuals with known admixed ancestry, the major component of their declaration was included in their results in all but one case. Based on these results, reporting guidelines were developed and subsequently evaluated using the Admixture Predictions of additional samples. This paper discusses the development and evaluation of these reporting guidelines, along with an implementation plan for forensic casework.

Utility of North Atlantic Right Whale Museum Specimens for Assessing Changes in Genetic Diversity.

We examined six historical specimens of the endangered North Atlantic right whale (Eubalaena glacialis) using DNA isolated from documented baleen plates from the late nineteenth and early twentieth centuries. Sequences from the mitochondrial DNA (mtDNA) control region from these samples were compared with those from a near-exhaustive survey (269 of approximately 320 individuals) of the remaining right whales in the western North Atlantic Ocean. Our results suggest that there has been only relatively modest change in maternal lineage diversity over the past century in the North Atlantic right whale population. Any significant reduction in genetic variation in the species most likely occurred prior to the late nineteenth century. One historical specimen was from the last documented female capable of propagating one of the maternal lineages in the population today; no females in the existing population have been found to carry this mtDNA haplotype. Analysis of the only specimens from the eastern North Atlantic right whale population ever to be examined revealed that eastern and western North Atlantic right whales may not have been genetically differentiated populations. Loss of gene diversity experienced by North Atlantic right whales over the last century has been modest, and the six decades of protection have been successful in maintaining much of the maternal lineage diversity that was present in the late nineteenth century.

RESUMEN: Examinamos seis especímenes históricos de la ballena franca septentrional Eubalaena glacialis del Atlántico Norte, usando ADN aislado de placas de las barbas documentadas de finales de siglo diecinueve y principios del siglo veinte. Las secuencias del ADN mitocondrial (mtADN) de la región control de estas muestras comparadas con aquéllas de una muestra casi exhaustiva (269 de aproximadamente 320 individuos) de las ballenas francas remanentes en el océano Atlántico Norte Occidental. Nuestros resultados sugieren que solo ha habido ligeros cambios en la diversidad del linaje materno a lo largo del siglo pasado. Probablemente, cualquier reducción en la variación genética en las especies ocurrió antes del final del siglo diecinueve. Uno de los especímenes históricos fue de la última hembra documentada capaz de propagar uno de los linajes maternos en la población actual. Ninguna de las hembras en las poblaciones existentes ha sido identificada como portadora de este haplotipo de mtADN. El análisis de los especímenes de la población de ballenas del Atlántico Norte Oriental examinados revelan que las ballenas francas del este y del oeste del Atlántico Norte podrían no haber sido poblaciones genéticamente diferentes. La pérdida de diversidad genética experimentada en las poblaciones de ballena franca del Atlántico Norte a lo largo del siglo pasado ha sido modesta y las seis décadas de protección han sido exitosas en el mantenimiento de la mayoría de la diversidad del linaje materno que estaba presente a finales del siglo diecinueve.