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• We explored worldwide genetic diversity and linkage disequilibrium for HLA-A,- E, -F, -G and -H. • Eleven novel HLA-H alleles were identified and validated, two of which possibly encoding a functional HLA protein. • We observed high LD between HLA-H and -A, and HLA-H and -G, and distinct worldwide allelic distribution of these genes. • Conversely, HLA-E and HLA-F had low LD, low allelic diversity and practically no difference in their distribution worlwide. The classical HLA class I genes (HLA Ia) were extensively studied because of their implication in clinical fields and anthropology. Less is known about worldwide genetic diversity and linkage disequilibrium for non-classical HLA class I genes (HLA Ib) and HLA pseudogenes. Notably, HLA-H, which is deleted in a fraction of the population, remains scarcely explored. The aims of this study were 1/ to get further insight into HLA-H genetic diversity and into how this variability potentially affects its expression and 2/ to define HLA Ib worldwide allelic diversity and linkage. Exome sequence data from the 1000 Genomes Project were used to define second field HLA-A, -E, -F, -G and -H typing using PolyPheMe software. Allelic and two-loci haplotype frequencies were estimated using Gene[Rate] software both at worldwide and continental levels. Eleven novel HLA-H alleles identified in exome data were validated by NGS performed on 25 genomic DNA samples from the same cohort. Phylogenetic analysis and frequency distribution of HLA-H alleles revealed three clades, each predominantly represented in Admixed American, European and East Asian populations, African populations and South Asian populations. Among these eleven novel alleles, two potentially encode complete transmembrane HLA proteins. We confirm the high LD between HLA-H and -A, and between HLA-H and -G , and show the three genes have distinct worldwide allelic distribution. Conversely, HLA-E and HLA-F both showed little LD, displayed restricted allelic diversity and practically no difference in their distribution across the planet. Our work thus reveals an unexpectedly high HLA-H genetic diversity, with alleles highly represented in Asia possibly encoding a functional HLA protein. Functional implication of these results remains to be explored, both in physiological and pathological contexts. [ABSTRACT FROM AUTHOR]

Vernicia montana Lour. is a deciduous tree species belonging to the family of Euphorbiaceae, distributed in southeast Asia. Here, we report and characterize the complete plastome of Vernicia montana Lour. The complete plastome is of 164,506 bp in length with a typical structure and gene content of angiosperm plastome, including two inverted repeat (IRs) regions of 27,965 bp, a large single-copy (LSC) region of 91,427 bp and a small single-copy (SSC) region of 17,149 bp. The plastome contains 130 genes, consisting of 81 protein-coding genes (six of which are repetitive in IR), 38 tRNA genes (seven of which are repetitive in IR), seven rRNA genes (5S rRNA, 4.5S rRNA, 23S rRNA and 16S rRNA) (three of which are repetitive in the IR), and four pseudogenes. The overall G/C content in the plastome of Vernicia montana Lour. is 35.8%. The complete plastome sequence of montana Lour. will provide a useful resource for the conservation genetics of this species as well as for phylogenetic studies in Euphorbiaceae. [ABSTRACT FROM AUTHOR]

Leprosy, a chronic human disease with potentially debilitating neurological consequences, results from infection with Mycobacterium leprae. This unculturable pathogen has undergone extensive reductive evolution, with half of its genome now occupied by pseudogenes. Using comparative genomics, we demonstrated that all extant cases of leprosy are attributable to a single clone whose dissemination worldwide can be retraced from analysis of very rare single-nucleotide polymorphisms. The disease seems to have originated in Eastern Africa or the Near East and spread with successive human migrations. Europeans or North Africans introduced leprosy into West Africa and the Americas within the past 500 years.