MtDNA sequence variation and haplogroup status in current and past laboratory personnel.

Note: Sequence variation of each individual was determined from a single hair (with the exception of samples 10 and 22 in which genomic DNA from whole blood was used) and was scored relative to the Cambridge Reference Sequence (CRS) [3]. Suffixes Y and A/C meant heteroplasmy for C and T, A and C, at the respective site. Suffixes A and C indicated transversions; “ins” and “del” indicated insertions and deletions, respectively. Indels (insertion/deletion) were recorded at the last possible site. Length mutations of the C-tract in regions 16184–16193 and 303–309 were not included. All samples had 315+C in the second hypervariable segment of mtDNA control region. The haplogroup status of the samples and geographic origin of the haplogroups were estimated according to the world mtDNA phylogeny as known to date [46]–[51], [54].