Figure 1. Amino acid alignment of avian CLOCK polyQ alleles.

Alignment includes sequences from Barn Swallows (Hirundo rustica; Hr) together with published Blue Tit (Cyanistes caeruleus; Cc), Great Tit (Parus Major; Pm), Bluethroat (Luscinia svecica; Ls) and Tree Swallow (Tachycineta bicolor; Tb). For each sequence the species name and number of Clock poly-Q repeats are shown. The predicted protein sequences of Barn Swallow Clock poly-Q repeats only differ in the number of CAG codon (coded by Q) repeats (The first and last glutamine (Q) amino acids in the poly-Q repeat were coded by CAA codons). Q residues coded by CAA are underlined and lower-case Qs are within-population polymorphic site encoded by either CAA or CAG. Asterisk indicates identical amino acids in the poly-Q flanking region between the all sequences.