It is tempting to ascribe the other mental disorders present in 22q11DS to alterations in signaling pathways related to neuronal functioning, and/or pathways known to be disturbed in neuropsychiatric syndromes, such as axonal guidance signalling and Huntington's disease signalling, neuregulin signalling, and neurotrophin signalling. The gene discussed is BDNF; the disease is juvenile Huntington disease.