115 validated SNPs explained less than 7% of the variance of height. Many phenotypes had very low proportions of variance explained. The lowest explained variance was found for ankle-brachial index (only 1 SNP was genome-wide significant and explained <0.1% of the total genetic variance). For most phenotypes there is apparently a substantial number of additional but yet undiscovered loci, which could increase the portion of the genetic variance explained (78), as we discuss in Part 2.
