02041nas a2200277   4500000000100000008004100001260001200042653000900054653002100063653002500084653002000109653001200129653001700141100001400158700001200172700001000184700001300194700001000207700001200217245007300229856007000302300001300372490000800385520135600393022001401749       2020                            d  c11/202010aFFPE10aHansen's disease10aMycobacterium leprae10aPacific Islands10aleprosy10awhole genome1 aBlevins K1 aCrane A1 aLum C1 aFuruta K1 aFox K1 aStone A00aEvolutionary history of Mycobacterium leprae in the Pacific Islands.  uhttps://royalsocietypublishing.org/doi/pdf/10.1098/rstb.2019.0582  a201905820 v3753 a<p>As one of the oldest known human diseases, leprosy or Hansen's disease remains a public health concern around the world with over 200 000 new cases in 2018. Most human leprosy cases are caused by , but a small number of cases are now known to be caused by , a sister taxon of . The global pattern of genomic variation in  is not well defined. Particularly, in the Pacific Islands, the origins of leprosy are disputed. Historically, it has been argued that leprosy arrived on the islands during nineteenth century colonialism, but some oral traditions and palaeopathological evidence suggest an older introduction. To address this, as well as investigate patterns of pathogen exchange across the Pacific Islands, we extracted DNA from 39 formalin-fixed paraffin-embedded biopsy blocks dating to 1992-2016. Using whole-genome enrichment and next-generation sequencing, we produced nine  genomes dating to 1998-2015 and ranging from 4-63× depth of coverage. Phylogenetic analyses indicate that these strains belong to basal lineages within the  phylogeny, specifically falling in branches 0 and 5. The phylogeographical patterning and evolutionary dating analysis of these strains support a pre-modern introduction of  into the Pacific Islands. This article is part of the theme issue 'Insights into health and disease from ancient biomolecules'.</p>  a1471-2970