(A) Allelic transcript ratios (±SEM) observed in 16 CEPH cell lines, for 10 transcript SNPs covering six genes across the 5q31 cytokine cluster. Four transcript SNPs in complete linkage disequilibrium across IL13 demonstrate consistent ATRs in all cell lines tested, suggesting that these results are real and not a product of asymmetrical primer affinity or extension reaction bias. (B) Allelic transcript ratios observed in 22 CEPH cell lines used in the HapMap resource show more variation in ATR for IL13 (using rs20541 as transcript SNP) than for IRF1 (using rs839), in both non-activated (N/A) and activated (A) cell aliquots. In each plot, the median allelic transcript ratio, the interquartile range, and the full range are shown for the group of cells assayed.
