Fig. 1 – Phylogeny of MCHR1 and MCHR1-like
Depicted here is the sequence-level variation found between tawny owl
colour morphs in MCHR1 loci and the respective phylogenetic
contextualization which suggests a duplication event prior to speciation
and a putative role of MCHR1-like as a pseudogene. We focused the
alignments on the regions where tawny owl’s colour-specific SNPs were
detected.
Fig. 2 – Single and combined effect of GWAS identified
genotypes on tawny owl coloration
The multiple GWAS approaches detected 2 loci significantly associated
with colour phenotypes. Here we show their effect size via the
percentage of individuals with genotype combinations of candidate loci
for each morph. We did it for individual locus (outside the Punnett
square diagram) and for combination of loci (Punnett square). Note that
“N” represents the number of individuals carrying each respective
genotype and/or genotype combinations. The genomic landscape on which
candidate loci was found in the tawny owl genome (shown by a thin red
bar) is depicted parallel to Punnett’s square axis. Yellow polygons
represent exons and blue polygons introns as predicted by the annotation
tool. Below the Punnett square diagram, we present the orthology of the
β-keratin (BISK1)-FTCD-CO6A2 region across bird genomes, whose accession
number can be consulted in the supplemental information document.
Fig. 3 – Hypothetical framework to
investigate the molecular basis of melanin-associated
phenotypes
In this figure we attempt to propose research directions to investigate
whether the molecular basis of melanin-associated phenotypes is linked
to structural variation, as our results suggest, driven by regulatory
mechanisms of a conserved gene region, such as the differential gene
expression found in barn owls, or epigenetic mechanisms yet to be found.
We further explained our next research avenues in the tawny owl system
specifically focused on the findings of this work (depicted with stars).