Abstract
We performed a meta-analysis of the newly assembled Komodo dragon (Varanus komodoensis) genome to characterize the major histocompatibility complex (MHC) of the species. The MHC gene clusters of the Komodo dragon are gene dense, complex, and contain counterparts of many genes of the human MHC. Our analysis identified 20 contigs encompassing ~ 6.9 Mbp of sequence with 223 annotated genes of which many are predicted orthologs to the genes of the human MHC. These MHC contigs range in size from 13.2 kb to 21.5 Mbp, contain an average of one gene per 30 kb, and are thought to occur on at least two chromosomes. Eight contigs, each > 100 kb, could be aligned to the human MHC based on gene content, and these represent gene clusters found in each of the recognized mammalian MHC subregions. The MHC of the Komodo dragon shares organizational features of other non-mammalian taxa. Multiple class Iα and class IIβ genes are indicated, with linkage between classical class I and immunoproteasome genes and between framework class I genes and genes associated with the mammalian class III subregion. These findings are supported in both Komodo genome assemblies and provide new insight into the MHC organization of these unique squamate reptiles.
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251_2021_1217_MOESM1_ESM.pdf
Supplementary file1: Suppl Fig. 1. Alignment of predicted gene transcripts to sequence contigs of the GS assembly of the Komodo dragon genome. (PDF 112 KB)
251_2021_1217_MOESM2_ESM.tiff
Supplementary file2: Suppl Fig. 2. Idiogram of sequence contigs of the Komodo dragon (Virginia Tech, VT assembly) aligned to the human MHC. Dashed lines connect predicted gene orthologs. VT contigs are drawn to scale and orientation of genes within the contigs is denoted by color (green + strand and red – strand). (TIFF 3272 KB)
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Reed, K.M., Settlage, R.E. Major histocompatibility complex genes and locus organization in the Komodo dragon (Varanus komodoensis). Immunogenetics 73, 405–417 (2021). https://doi.org/10.1007/s00251-021-01217-6
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DOI: https://doi.org/10.1007/s00251-021-01217-6