A novel variant in SLC16A2 associated with typical Allan-Herndon-Dudley syndrome: a case report

TLDR: Wang et al. as discussed by the authors reported a novel splicing mutation in the SLC16A2 gene in an 18-month-old male patient with allan-herndon-dudley syndrome.

Abstract: Allan-Herndon-Dudley syndrome (AHDS) is an X-linked recessive neurodegenerative disorder caused by mutations in the SLC16A2 gene that encodes thyroid hormone transporter. AHDS has been rarely reported in China.This study reported a novel splicing mutation in the SLC16A2 gene in an 18-month-old male patient with AHDS. The patient was born to non-consanguineous, healthy parents of Chinese origin. He passed new-born screening for hypothyroidism, but failed to reach developmental milestones. He presented with hypotonia, severe mental retardation, dysarthria and ataxia. Genetic analysis identified a novel splicing mutation, NM_006517.4: c.431-2 A > G, in the SLC16A2 gene inherited from his mother. The patient received Triac treatment, (triiodothyroacetic acid), a thyroid hormone analogue for 3 months. Triac treatment effectively reduced serum TSH concentrations and normalized serum T3 concentrations in the patient.This study reported the first case of AHDS treated by Triac in China. And the study expanded the mutational spectrum of the SLC16A2 gene in AHDS patients.