SHANK3 and premenstrual tension: Whereas the proportion of patients with SHANK3 variants in the PMS International Registry (which gathers genetic and clinical data from affected individuals around the world) is 8.6% (47 out of 546 with a genetically confirmed diagnosis), it rises to 25% (14 of 56) among the cases reviewed here (Fisher’s exact test, p = 0.00057).