Forensic identification of urine samples: a comparison between nuclear and mitochondrial DNA markers

Abstract

Urine samples from 20 male volunteers of European Caucasian origin were stored at 4 degrees C over a 4-month period in order to compare the identification potential of nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) markers. The amount of nDNA recovered from urines dramatically declined over time. Consequently, nDNA likelihood ratios (LRs) greater than 1,000 were obtained for 100, 70 and 55% of the urines analysed after 6, 60 and 120 days, respectively. For the mtDNA, HVI and HVII sequences were obtained for all samples tested, whatever the period considered. Nevertheless, the highest mtDNA LR of 435 was relatively low compared to its nDNA equivalent. Indeed, LRs obtained with only three nDNA loci could easily exceed this value and are quite easier to obtain. Overall, the joint use of nDNA and mtDNA markers enabled the 20 urine samples to be identified, even after the 4-month period.

Elevated and similar urinary testosterone/epitestosterone ratio in all samples of a competition testing: Suspicion of a manipulation

“…Very recently, we developed in our laboratories a methodology using nuclear as well as mitochondrial DNA markers to prove that no manipulations of urine samples occurred in clinical, toxicological or doping control tests [11,12]. When applied to all seven urine samples, we found that three samples (samples 1, 1 0 and 1 00 , Fig.…”

“…Genetic profiling was used to determine whether several urines could come from the same athlete [11,12]. For this purpose, total DNA was extracted from urine samples using a phenol-chloroform protocol [13].…”

Comparison of laser and mercury-arc lamp for the detection of body fluids on different substrates

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Biological traces at the crime scene

“…Tragovi mokraće uzimaju se samo ako su pronađeni u većoj količini (najmanje 10 mL) u posudi/ kanti/čaši/boci 44 . Ne uzimaju se tragovi mokraće koji su pronađeni na površinama ili upijeni tragovi mokraće.…”