In contrast to functional coding variants, RegulomeDB allows us to focus on noncoding variants that are likely to directly affect binding (Category 1 and 2), resulting in 70,216 SNVs (18,842 [0.51%] and 51,374 [1.47%] in Categories 1 and 2, respectively). Of these, 25,654 (0.69%) are homozygous and likely to affect gene expression of both alleles. Therefore, many variants are predicted to affect regulatory elements in noncoding regions, and this figure is more than 30 times higher than those that are predicted to disrupt gene function using current methods. However, these regulatory variants can only be associated with altered expression levels of genes and may not be as disruptive as the damaging variants in coding regions which may alter or destroy gene products.
