STRmix™ collaborative exercise on DNA mixture interpretation.

An intra and inter-laboratory study using the probabilistic genotyping (PG) software STRmix™ is reported. Two complex mixtures from the PROVEDIt set, analysed on an Applied Biosystems™ 3500 Series Genetic Analyzer, were selected. 174 participants responded.

A simple DNA extraction method for marijuana samples used in amplified fragment length polymorphism (AFLP) analysis.

As a first step in developing a molecular method for the individualization of marijuana samples, we evaluated a plant DNA extraction kit. The QIAGEN plant DNeasy method uses a spin column format for recovery of DNA and is effective for obtaining high molecular weight DNA from leaf, flower (bud), and seed samples of marijuana. The average DNA yield was 125-500 ng per 100 milligrams of fresh plant tissue.

Analysis of salivary DNA evidence from a bite mark on a body submerged in water.

A female body was recovered after approximately 5.5 h in a river with slow-moving current. On the victim's right breast, a patterned injury was discovered and determined to be from human adult teeth.

Removal of a PCR inhibitor and resolution of DNA STR types in mixed human-canine stains from a five year old case.

The analysis of biological trace evidence from a reopened investigation into a 1991 murder from Vernon, B.C. revealed mixed human and dog bloodstains on blue jean pants that contained a PCR inhibitory substance.