Development of a forensic DNA research grade test material.

Advancements in forensic DNA typing technology and methods have increased sensitivity and, while beneficial, carry the weight of more challenging profile interpretation. In response, the forensic DNA community has often requested more complex reference materials to address commonly encountered measurement and interpretation issues such as complex DNA mixtures, DNA degradation, and PCR inhibition. The National Institute of Standards and Technology (NIST) released Research Grade Test Material 10235: Forensic DNA Typing Resource Samples to support the forensic DNA community.

Recommendations of the DNA Commission of the International Society for Forensic Genetics (ISFG) on short tandem repeat sequence nomenclature.

The DNA Commission of the International Society for Forensic Genetics (ISFG) has developed a set of nomenclature recommendations for short tandem repeat (STR) sequences. These recommendations follow the 2016 considerations of the DNA Commission of the ISFG, incorporating the knowledge gained through research and population studies in the intervening years. While maintaining a focus on backward compatibility with the CE data that currently populate national DNA databases, this report also looks to the future with the establishment of recommended minimum sequence reporting ranges to facilitate interlaboratory comparisons, automated solutions for sequence-based allele designations, a suite of resources to support bioinformatic development, guidance for characterizing new STR loci, and considerations for incorporating STR sequences and other new markers into investigative databases.

Harmonizing the forensic nomenclature for STR loci D6S474 and DYS612.

The autosomal STR D6S474 and the Y-chromosomal STR DYS612 have been reported in multiple ways in the forensic literature, with differences in both the bracketed repeat structures and counting of numerical length-based capillary electrophoresis (CE) alleles. These issues often come to light when STR loci are introduced in commercial assays and results compared with historical publications of allele frequency data, or multiple assays are characterized with reference materials. We review the forensic literature and other relevant information, and provide suggestions for the future treatment of each STR.

US Population Data for 94 Identity-Informative SNP Loci.

The US National Institute of Standards and Technology (NIST) analyzed a set of 1036 samples representing four major US population groups (African American, Asian American, Caucasian, and Hispanic) with 94 single nucleotide polymorphisms (SNPs) used for individual identification (iiSNPs). The compact size of iiSNP amplicons compared to short tandem repeat (STR) markers increases the likelihood of successful amplification with degraded DNA samples. Allele frequencies and relevant forensic statistics were calculated for each population group as well as the aggregate population sample.

Sequence-based allelic variations and frequencies for 22 autosomal STR loci in the Lebanese population.

This is the first study that characterizes the sequence-based allelic variations of 22 autosomal Short Tandem Repeat (aSTR) loci in a population dataset collected from Lebanon. Genomic DNA extracts from 195 unrelated Lebanese individuals were amplified with PowerSeq 46GY System Prototype. Targeted amplicons were subjected to DNA library preparation and sequenced on the Verogen MiSeq FGx Sequencing System.