The disease is due to mutations in the SLC16A2 gene, which encodes for the thyroid hormones transporter MCT8. This protein is particularly important for the active transport of thyroid hormones across Blood Brain Barrier and for their import into neural cells where it performs its main functions, especially for the proper development of Central Nervous System (CNS).
So far reported pathogenic variants are missense, nonsense, splice-site, small deletions and insertions. Most harmful mutations are those that result in a loss of function, causing a severe decrease in activity or complete deactivation of the MCT8 transporter. Mutations that only partially deactivate the protein may result in less severe symptoms.
SLC16A2