Variable nucleotide tandem repeat (VNTR) typing of two palaeopathological cases of lepromatous leprosy from Mediaeval England

Using ancient DNA methods, we have examined in detail two archaeological cases of leprosy from Mediaeval England. The first was a child skeleton with rhino-maxillary changes typical of lepromatous leprosy (LL). The second case was the skeleton of a male adult who showed both typical rhino-maxillary changes and osteitis/periostitis on the leg and foot bones. Bone powder was sampled from both cases and DNA extracts were prepared. These were subjected to a series of polymerase chain reactions (PCRs) specific for regions on the Mycobacterium leprae genome. The repetitive element RLEP was used for confirmation of M. leprae DNA and then three polymorphic regions were successfully amplified and sequenced to determine the number of variable nucleotide tandem repeats (vntr) at these loci. These were the microsatellite regions ML2344 and ML2172 and the minisatellite region ML0058. Genotyping data from the strains preserved within the skeletal remains were compared with those obtained for a reference strain of M. leprae. Variation at these three loci was found between both burials and the reference strain, indicating that vntr typing of LL cases from the archaeological record is a useful way of confirming disease and an additional means of authenticating aDNA data. This demonstrates the feasibility of targeting multiple loci for phylogenetic studies of leprosy strains from archival sources.