FIGURE 2.

A 1 Mb region on chromosome 11 is associated with autosomal barring. (a) Segregation of pigmentation phenotypes among backcross progeny. Photograph credit: David Gourichon, INRA. (b) Genome-wide screen for genetic differentiation between three different pools (“autosomal barred,” “unclear” and “wild-type”) of Fayoumi/Light Brown Leghorn backcross offspring using F_ST values in 30 kb sliding windows. (c) SNP scoring within 20 Mb and 3.5 Mb regions on chromosomes 1 and 11, respectively, in parents (P) and offspring progeny (BC) showing autosomal barring (AB), “unclear” patterning or wild-type plumage. The positions of MC1R and SOX10 are indicated. Please note that a higher density of SNPs was used toward the end of chromosome 11 visually suggesting that the 1 Mb interval is taking up half of the 3.5 Mb region. The borders of the 1 Mb non-recombining interval are based on a single recombinant. Yellow color indicates homozygosity for an allele inherited from the wild-type Light Brown Leghorn parental (WT), whereas red indicates homozygosity for a Fayoumi-derived allele. Orange color indicates heterozygosity. The panel for chromosome 11 represents 18 SNPs with the first situated at 15.8 Mb and the last one at 19.7 Mb. Forty-six SNPs were placed within the 20 Mb region on chromosome 1 with the first SNP located at 40 Mb and the last at 59.8 Mb. White fields indicate missing genotypes.