Fig. 1.

Haplotype structure of the IL-1 receptor-associated kinase 4 (IRAK4) gene. Haplotypes of the IRAK4 gene were inferred from unphased genotype data from 23 Caucasians using PHASE software. Columns are polymorphic sites of IRAK4. Rows are haplotypes of IRAK4 ordered by phylogenetic relationship. Light grey/yellow boxes are minor alleles and dark grey/blue boxes are major alleles. Cladistic relationships of IRAK4 haplotypes were determined using MEGA2 phylogenetic software. There are 4 major haplotype clades of IRAK4, marked clades 1 through 4. C23338G, T24472C, and G29429A were chosen as a haplotype clade tag single nucleotide polymorphisms (htSNP) to distinguish between the 4 major haplotype clades.