Elevated frequencies of TERT promoter, TP53, PTEN and PIK3CA mutations have been observed in ATCs with respect to PDTCs; ATCs also have NF1, NF2, ATM, CDKN2A, CDKN2B and RB1 mutations. The gene discussed is CDKN2B; the disease is Ehlers-Danlos syndrome, musculocontractural type.