Interestingly, severe regression in both language and social skills and adaptive functions (loss of motor skills, loss of independent eating and dressing, anorexia, loss of weight and urinary incontinence) have previously been reported in patients at different stages in development with a partial deletion or a single mutation of SHANK3 gene [3, 9]: during childhood [11, 12, 31], in adolescence [1, 15, 16, 32] or in adulthood [17, 18]. This evidence concerns the gene SHANK3 and Anorexia.