TY - JOUR T1 - Low parental melatonin levels increases autism spectrum disorder risk in children JF - bioRxiv DO - 10.1101/046722 SP - 046722 AU - Wiebe Braam AU - Friederike Ehrhart AU - Chris T. Evelo AU - Anneke P.H.M. Maas AU - Marcel G. Smits AU - Leopold Curfs Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/04/02/046722.abstract N2 - Background: Low melatonin levels are a frequent finding in autism spectrum disorder (ASD) patients. Melatonin is also important for normal neurodevelopment and embryonic growth. As a free radical scavenger and antioxidant melatonin is highly effective in protecting DNA from oxidative damage. Melatonin deficiency, possibly due to low CYP1A2 activity, could be a major factor, and well a common heritable variation. ASD is already present at birth. As the fetus does not produce melatonin, low maternal melatonin levels should be involved.Methods: We measured 6-sulfatoxymelatonin in urine of mothers of a child with ASD that attended our sleep clinic for people with an intellectual disability (ID), and asked for parental coffee consumption habits, as these are known to be related to CYP1A2 activity.Results: 6-Sulfatoxymelatonin levels were significantly lower in mothers than in controls (p = 0.005), as well as evening coffee consumption (p = 0.034). In mothers with a second child with ASD and/or ID, 6-sulfatoxymelatonin levels were lower compared to mothers with one child with ASD (p = 0.084),Conclusions: Low parental melatonin levels, likely caused by low CYP1A2 activity, seem to be a major contributor to ASD and possibly ID etiology.ASDautism spectrum disorderIDintellectual disability6-SM6-sulfatoxymelatonin ER -