SLC39A8 and insomnia: Individual daytime sleepiness increasing alleles at PATJ and PLCL1 were also associated with morning chronotype; loci at metabolism regulatory genes KSR2, LOC644191/CRHR1, and SLC39A8 with self-reported sleep duration (KSR2 with increased sleep duration, LOC644191/CRHR1 with long sleep, and SLC39A8 with short sleep); LMOD1 and LOC644456/LOC730134 with both insomnia and short sleep duration; and at the orexin/hypocretin receptor HCRTR2 with both morning chronotype and short sleep duration, suggesting common genetic factors.