Abstract
The MHC genes on human chromosome 6 are located within one of the best-characterised paralogy regions of the human genome. Numerous genes mapping around this location, 6p21, have paralogues at one, two or three other chromosomal locations on HSA 1, 9 and 19. The similarity between these four chromosomal regions suggests the linkages may have adaptive significance, and/or they may be echoes of segmental or genome duplication in human ancestry. Here, we show that six amphioxus cosmids, containing genes orthologous to those from the human MHC-linked paralogy regions, map to a single amphioxus chromosome. The composition of the MHC-linked genomic region, therefore, pre-dates vertebrate origins.
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Acknowledgements
This research was funded by the Fundação para a Ciência e a Tecnologia, Portugal (BD/21818/99 to LFCC) and the BBSRC (to RFF and PWHH). We thank Pierre Pontarotti and colleagues for helpful discussions.
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Castro, L.F.C., Furlong, R.F. & Holland, P.W.H. An antecedent of the MHC-linked genomic region in amphioxus. Immunogenetics 55, 782–784 (2004). https://doi.org/10.1007/s00251-004-0642-9
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DOI: https://doi.org/10.1007/s00251-004-0642-9