GABRA2 and sleep disorder: Additional novel loci were identified within or near genes with known actions on sleep–wake control regulation or that are associated with sleep disorders (e.g. PLCL1 (ref. 26), GABRA2 (ref. 27), BTBD9 (ref. 28), HTR7 (ref. 29), RAI1 (ref. 30)), metabolic traits (e.g. GCKR31, SLC39A8 (ref. 32)), and psychiatric traits (e.g. AGAP1 (ref. 33), CACNA1C34).