eLife Assessment
This important manuscript presents a thorough analysis of the evolution of Major Histocompatibility Complex gene families across primates. A key strength of this analysis is the use of state-of-the-art phylogenetic methods to estimate rates of gene gain and loss, accounting for the notorious difficulty to properly assemble MHC genomic regions. Overall the evidence for the authors' conclusions – that there is considerable diversity in how MHC diversity is deployed across species – is compelling.