This is in agreement with two previous studies reporting associations between a high frequency of the HLA-DRB1 *11 allele and: (i) autism risk and concomitant decrease in CD4+ naive and increase in CD4+ memory T cells in Italian patients36; and (ii) autism risk and family history of autoimmune disorders in patients of Saudi Arabian origin48. The gene discussed is CD4; the disease is Autoimmunity.