NOTCH3 and migraine disorder: The hypomorphic nature of the NOTCH3A1604T receptor may, however, suggest that the vasculature is affected because loss of NOTCH3 function causes a gradual loss of VSMC in the mouse.18,19 Vascular impairment may in turn result in migraine and WML but with incomplete penetrance and possibly of a different type than in CADASIL, given the cysteine-sparing nature of the A1604T mutation.