Figure 2

Amino acid positions under positive selection. A sequence logo showing the relative frequencies of various amino acids in particular positions of the examined fragment of the MHC class IIB 2^nd exon. The plot is based on sequences of all putative expressed alleles. Antigen Binding Sites (ABS) are shaded, and positions under positive selection as revealed by the Bayes Empirical Bayes (BEB) procedure are indicated with asterisks.