Forensic genetic genealogy using microarrays for the identification of human remains: The need for good quality samples - A pilot study.

The successful application of forensic genetic genealogy (FGG) to identify Jane and John Doe cases in the United States has raised the prospect of using the technique in Australia to assist in the reconciliation of unidentified human remains (UHRs) with long term missing persons. A study was conducted to explore the feasibility of FGG using whole genome array (WGA) data from both pristine control samples as well as compromised casework samples, with the view to explore how DNA quantity and quality impacted on the ability to generate search results when compared to a genetic genealogy database, such as GEDmatch. From this study, several insights were gained as to the impact DNA quantity and degradation had on the percentage of SNPs genotyped and heterozygote/homozygote ratio - which are critical for successful matching outcomes. It was noted in this study (using a control sample) that successful matching occurred when genotyping errors were 5% or less. Two UHR cases were matched to kits on GEDmatch PRO, which provided investigative leads for identification purposes. The effectiveness of the FGG approach to match casework samples (as well as volunteer samples used in the study) is indicative of the usage of 'direct-to-consumer' (DTC) genetic testing by Australians. Given the (often) limited availability of casework samples, findings from this study will assist Australian agencies considering the use of FGG, to determine if WGA is a suitable method for their application.

Examples of kinship analysis where Profiler Plus™ was not discriminatory enough for the identification of victims using DNA identification.

The identification of the victims of the 2009 Victorian bushfires disaster, as in other mass disasters, relied on a number of scientific disciplines - including DNA analysis. As part of the DVI response, DNA analysis was performed to assist in the identification of victims through kinship (familial matching to relatives) or direct (self source of sample) matching of DNA profiles. The majority of the DNA identifications made (82%) were achieved through kinship matching of familial reference samples to post mortem (PM) samples obtained from the victims. Although each location affected by the bushfires could be treated as a mini-disaster (having a small closed-set of victims), with many such sites spread over vast areas, DNA analysis requires that the short tandem repeat (STR) system used be able to afford enough discrimination between all the DVI cases to assign a match. This publication highlights that although a 9-loci multiplex was sufficient for a DVI of this nature, there were instances that brought to light the short comings of using a 9-loci multiplex for kinship matching--particularly where multiple family members are victims. Moreso it serves to reinforce the recommendation that a minimum of 12 autosomal STR markers (plus Amelogenin) be used for DNA identification of victims which relies heavily on kinship matching.

The importance of Guthrie cards and other medical samples for the direct matching of disaster victims using DNA profiling.

The identification of disaster victims through the use of DNA analysis is an integral part of any Disaster Victim Identification (DVI) response, regardless of the scale and nature of the disaster. As part of the DVI response to the 2009 Victorian Bushfires Disaster, DNA analysis was performed to assist in the identification of victims through kinship (familial matching to relatives) or direct (self source sample) matching of DNA profiles. Although most of the DNA identifications achieved were to reference samples from relatives, there were a number of DNA identifications (12) made through direct matching. Guthrie cards, which have been collected in Australia over the past 30 years, were used to provide direct reference samples. Of the 236 ante-mortem (AM) samples received, 21 were Guthrie cards and one was a biopsy specimen; all yielding complete DNA profiles when genotyped. This publication describes the use of such Biobanks and medical specimens as a sample source for the recovery of good quality DNA for comparisons to post-mortem (PM) samples.