Schematic representation of the predicted protein domains and genomic organization of the porcine <i>MUC13</i> gene encoding two transcripts: <i>MUC13A</i> (upper panel) and <i>MUC13B</i> (middle panel).

<p>Exons are indicated by boxes and introns by thin lines. The distinct PTS regions of two <i>MUC13</i> transcripts are highlighted by different colors. The gaps on exon 2 indicate the unknown number of tandem repeats in the PTS region that are enriched in proline, threonine and/or serine. We assumed the repeat number as 100 for the analyses of MUC13 PTS domains. The <i>O</i>-glycosylated sites are marked only in the PTS region of MUC13B as predicted by DictyOGlyc <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044573#pone.0044573-Gupta1" target="_blank">[45]</a>. The diagnostic Indel for <i>MUC13A</i> and <i>MUC13B</i> alleles and the most significant SNP (g.28784 T>C) in the association studies of outbred populations are depicted at the corresponding sites. The sizes are drawn to scale.