No abstract

The polymorphism of the two hypervariable segments (HVI and HVII) of the control region of mtDNA was analyzed in a population of 154 unrelated individuals from south west Switzerland using a fluorescent based capillary electrophoresis sequencing method. In our population data of 154 random individuals, 137 mtDNA types were observed. Of these, 124 sequences were observed only in one individual whereas 10 sequences were observed in 2 individuals, 2 sequences in 3 individuals and 1 sequence in 4 individuals. The probability of two unrelated individuals having the same sequence was 0.84%. The results were compared with four other Caucasian populations. Furthermore, the usefulness of the mtDNA sequencing was tested, for exclusion and inclusion, in 18 forensic cases including 69 evidence samples and 44 reference samples. Despite the fact that 55% of the evidence samples yielded a negative result for the nuclear DNA with the human dot quantitation system, the success rate of the mtDNA sequencing was 71.0%. This validation study proves the great usefulness and sensitivity of the mtDNA sequencing technique using nested PCR and fluorescent capillary electrophoresis.

No abstract

No 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.