Expression differences between exonic SNP alleles. SNP alleles that are heterozygous in an individual (those with a DNA reference allele frequency of 0.5) are considered differentially expressed when the reference allele in mRNA has a frequency of ≤0.4 or ≥0.6 (white background), which corresponds to an allele ratio of ≥1.5. (A) DNA and RNA reference allele frequencies for exonic SNPs for individual 9. In this individual, there were 591 heterozygous exonic SNPs, and 108 (18%) of these were differentially expressed. (B) Heterozygous SNP alleles display three distinct expression patterns in the 12 unrelated individuals: monoallelic expression for ss24225694 in ZNF463; differential expression with the same allele expressed at a higher level in each heterozygous individual for ss24290540 in FLJ21069 and ss23668266 in C1orf38; and inconsistent favoring of alleles for ss24515622 in D21S2056E.
