First assessment of MHC diversity in wild Scottish red deer populations

Control and mitigation of disease in wild ungulate populations is one of the major challenges in wildlife 49 management. Despite the importance of the Major Histocompatibility Complex (MHC) genes for immune 50 response, assessment of diversity on these genes is still rare for European deer populations. Here, we conducted 51 the first assessment of variation at the second exon of the MHC DRB in wild populations of Scottish highland red 52 deer, the largest continuous population of red deer in Europe. Allelic diversity at these loci was high, with 25 53 alleles identified. Selection analyses indicated c. 22% of amino acids encoded found under episodic positive 54 selection. Patterns of MHC allelic distribution were not congruent with neutral population genetic structure 55 (estimated with 16 nuclear microsatellite markers) in the study area; the latter showing a marked differentiation 56 between populations located at either side of the Great Glen. This study represents a first step towards building an 57 immunogenetic map of red deer populations across Scotland to aid future management strategies for this 58 ecologically and economically important species.