Welcome - Allan Herndon Dudley Syndrome MCT8 (AHDS) Community

What is Allan Herndon Dudley Syndrome MCT8 (AHDS) ?

Allan-Herndon- Dudley (AHDS) is caused by a mutation of the MCT8 gene which is responsible for the transport of Thyroid Hormones to the brain. It is an X-link inherited mutation that only affects male patients. Because of the mutation, the blood brain barrier does not recognize the carrier and it doesn’t allow its passage into the brain. As a result, the brain doesn’t develop properly. Lack of thyroid hormones in the brain is the main cause for mental delay. So, the hormones are stuck in the body creating toxicity in the blood and putting pressure on vital organs.


Allan-Herndon-Dudley syndrome
Allan-Herndon syndrome
MCT8-specific thyroid hormone cell transporter deficiency
MCT8-THCT deficiency
mental retardation, X-linked, with hypotonia
THCT deficiency 

Allan Herndon Dudley Syndrome MCT8 (AHDS) Resources

More members stories

Latest Member Stories

Jaeden's Journey of Diagnosis

by mct8canada published 6 months ago

As the months progressed, Jaeden’s developmental delays were becoming apparent, and we knew something wasn’t right. He struggled physically and ver...

Cole's Story

by RareConnect team published 8 months ago

He was healthy and breastfed well so there were no concerns in the early days of his life. It wasn't until he was about 3 months old that it was n...

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