The presence of BRAF mutation, including BRAFV600E, is observed in ATC coexisting with PTC.37, 38, 39, 40 Notably, cases of BRAF mutation were identified in ATCs derived from BRAF-mutant PTCs,41 underscoring the engagement of BRAF mutation, particularly BRAFV600E, in the tumorigenesis of both ATC and PTC. The gene discussed is BRAF; the disease is Ehlers-Danlos syndrome, musculocontractural type.