MCT8-specific Thyroid Hormone Cell Transporter (THCT) Deficiency is a rare genetic condition caused by a change (mutation) in the MCT8 (Monocarboxylate transporter 8) gene. Common findings in these children include: developmental delay, poor head control, low muscle tone and unclear or no speech. Not everyone with this disorder has all the findings or is affected to the same degree. Patients (generally males) with this condition also have a thyroid hormone problem that is less severe in their mothers.

The MCT8 Organization is a group of parents whose sons are affected by the MCT8-specific THCT Deficiency. We are working alongside a medical team. Our goal is to provide educational material, support and advocacy for patients, families and the medical community on the MCT8-specific THCT Deficiency.