The loss of typical thyroid cell characteristics and functions, including expression of the thyroid-stimulating hormone (TSH) receptor (TSH-R), thyroglobulin (Tg), thyroid peroxidase (TPO), and sodium iodide symporter (NIS), defines the hallmark of ATCs, which are lethal malignancies with no effective therapy (1–3). This evidence concerns the gene TPO and Ehlers-Danlos syndrome, musculocontractural type.