The most significant SNPs associated with HD age at onset are located just 3’ to SOSTDC1, and also show significant eQTL (expression quantitative trait loci) signals for SOSTDC1 in the GTEx data set (http://www.gtexportal.org/home/eqtls/byGene?geneId=sostdc1&tissueName=All) (Fig 6) whereas none of these SNPs show evidence of association with expression of any of the other genes in the region. This evidence concerns the gene SOSTDC1 and Huntington disease.