Responding to the American Academy of Forensic Sciences vision, mission, and values statements: Comments, revisions, and proposed actions.

•We call for revisions to the current AAFS vision, mission, and values statements.•Truly aspirational statements will provide guiding principles for forensic scientists.•Revisions should meaningfully engage with issues of diversity and equity.•Our goal of pursuing justice should also extend to our practitioner community.•We envision AAFS committees of diverse membership making positive changes to the statements.

Teaching forensic science under conditions of humanitarian crisis: Toward a critically-informed experiential approach.

This article examines the use of critical pedagogy practices for teaching students the forensic science of migrant death and identification in the US borderland. Critical pedagogy, a philosophy of education that centers issues of social justice and human rights in the classroom, insists that teaching is inherently political, and challenges students to recognize and address power structures which perpetuate an unjust status quo. Drawing examples from qualitative data gathered during two field seasons in South Texas with the University of Indianapolis Forensic Science Team and narrative analysis of students team members' daily reflections about their work within structures designed to address the US border crisis, this article illuminates challenges and possibilities for teaching in learning in a context of mass violence.

DNA recovery and analysis from skeletal material in modern forensic contexts.

The generation of a DNA profile from skeletal remains is an important part of the identification process in both mass disaster and unidentified person cases. Since bones and teeth are often the only biological materials remaining after exposure to environmental conditions, intense heat, certain traumatic events and in cases where a significant amount of time has passed since the death of the individual, the ability to purify large quantities of informative DNA from these hard tissues would be beneficial. Since sampling the hard tissues for genetic analysis is a destructive process, it is important to understand those environmental and intrinsic factors that contribute to DNA preservation. This will serve as a brief introduction to these topics, since skeletal sampling strategies and molecular taphonomy have been discussed in depth elsewhere. Additionally advances in skeletal DNA extraction and analysis will be discussed. Currently there is great variation in the DNA isolation methods used by laboratories to purify DNA from the hard tissues; however, a standardized set of short tandem repeat (STR) loci is analyzed by many US laboratories to allow for comparisons across samples and jurisdictions. Recent advances have allowed for the generation of DNA profiles from smaller quantities of template DNA and have expanded the number of loci analyzed for greater discriminatory power and predictions regarding the geographic ancestry and phenotype of the individual. Finally, utilizing databases and expanding the number of comparison samples will be discussed in light of their role in the identification process.

Could Secondary DNA Transfer Falsely Place Someone at the Scene of a Crime?

The occurrence of secondary DNA transfer has been previously established. However, the transfer of DNA through an intermediary has not been revisited with more sensitive current technologies implemented to increase the likelihood of obtaining results from low-template/low-quality samples. This study evaluated whether this increased sensitivity could lead to the detection of interpretable secondary DNA transfer profiles. After two minutes of hand to hand contact, participants immediately handled assigned knives. Swabbings of the knives with detectable amounts of DNA were amplified with the Identifiler(®) Plus Amplification Kit and injected on a 3130xl. DNA typing results indicated that secondary DNA transfer was detected in 85% of the samples. In five samples, the secondary contributor was either the only contributor or the major contributor identified despite never coming into direct contact with the knife. This study demonstrates the risk of assuming that DNA recovered from an object resulted from direct contact.

Unexpected NRY chromosome variation in Northern Island Melanesia.

To investigate the paternal population history of populations in Northern Island Melanesia, 685 paternally unrelated males from 36 populations in this region and New Guinea were analyzed at 14 regionally informative binary markers and 7 short tandem repeat (STR) loci from the nonrecombining portion of the Y chromosome. Three newly defined binary markers (K6-P79, K7-P117, and M2-P87) aided in identifying considerable heterozygosity that would have otherwise gone undetected. Judging from their geographic distributions and network analyses of their associated STR profiles, 4 lineages appear to have developed in this region and to be of considerable age: K6-P79, K7-P117, M2-P87, and M2a-P22. The origins of K5-M230 and M-M4 are also confirmed as being located further west, probably in New Guinea. In the 25 adequately sampled populations, the number of different haplogroups ranged from 2 in the single most isolated group (the Aita of Bougainville), to 9, and measures of molecular diversity were generally not particularly low. The resulting pattern contradicts earlier findings that suggested far lower male-mediated diversity and gene exchange rates in the region. However, these earlier studies had not included the newly defined haplogroups. We could only identify a very weak signal of recent male Southeast Asian genetic influence (<10%), which was almost entirely restricted to Austronesian (Oceanic)-speaking groups. This contradicts earlier assumptions on the ancestral composition of these groups and requires a revision of hypotheses concerning the settlement of the islands of the central Pacific, which commenced from this region.