Sequence variation in melanocortin-1-receptor and tyrosinase-related protein 1 genes and their relationship with melanin-based plumage trait expression in Lesser Kestrel (Falco naumanni) males

Lesser kestrel males display inter-individual variation in melanin-based plumage traits, like ventral plumage colouration and breast/underwing spottiness. We explored whether such plumage variability was associated with single-nucleotide genetic polymorphisms of melanocortin-1-receptor (MC1R) and tyrosinase-related protein 1 (TYRP1), two genes involved in the melanogenesis pathway. No statistically significant associations between single-nucleotide mutations and male plumage traits emerged, though in some cases very rare (< 2%) homozygous mutated individuals displayed extreme plumage phenotypes. Hence, large inter-individual male Lesser Kestrel plumage variation, which is consistent between years and partly age related, was only marginally related to untranslated region and coding sequence variation of MC1R and TYRP1.