PIGQ and insomnia: Similarly, the insomnia-associated candidate regulatory variants at GWAS locus number 170 identified by our variant-to-gene mapping reside in an intron of WDR90 but loop across ~90 kb to the promoter region of two candidate effector genes farther away, NHLRC4 and PIG-Q, and to the NME4 promoter 258 kb away.