| Abstract: | Symptoms of a newly discovered X-chromosomal severe mental retardation disease were published by William Allan, Nash Herndon and Florence Dudley in 1944. Patients suffered from muscle weakness and a developmental delay not able to sit, walk and speak. In addition, they showed an endocrinological phenotype with abnormal thyroid hormone constellations. The reason for the Allan-Herndon-Dudley syndrome was found in a mutation of the monocarboxylate transporter 8 (MCT8, SLC16A2), a specific thyroid hormone transporter. |
