Allan-Herndon-Dudley syndrome
Findings
No curated finding names Allan-Herndon-Dudley syndrome yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A syndrome with neuromuscular involvement characterized by infantile hypotonia, muscular hypoplasia, spastic paraparesis with dystonic/athetoic movements, and severe cognitive deficiency.
Definition from the Mondo Disease Ontology (MONDO:0010354), read 2026-09-29. CC BY 4.0.
- Inheritance
- X-linked recessive inheritance
HPO, annotations 2026-09-02
Features
56 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- Axial hypotoniaHPOHP:0008936
- Very frequent (80% to 99% of cases)
- Intellectual disabilityHPOHP:0001249
- Very frequent (80% to 99% of cases)
- Abnormal pyramidal signHPOHP:0007256
- Frequent (30% to 79% of cases)
- Abnormality of thyroid physiologyHPOHP:0002926
- Frequent (30% to 79% of cases)
- AtaxiaHPOHP:0001251
- Frequent (30% to 79% of cases)
- Brain atrophyHPOHP:0012444
- Frequent (30% to 79% of cases)
- Choreoathetosis
Show the remaining 44
- Failure to thrive in infancyHPOHP:0001531
- Frequent (30% to 79% of cases)
- Feeding difficulties in infancyHPOHP:0008872
- Frequent (30% to 79% of cases)
- HyperhidrosisHPOHP:0000975
- Frequent (30% to 79% of cases)
- HyperreflexiaHPOHP:0001347
- Frequent (30% to 79% of cases)
- HypertensionHPOHP:0000822
- Frequent (30% to 79% of cases)
- HypokinesiaHPOHP:0002375
- Frequent (30% to 79% of cases)
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- SLC16A2HGNC:10923
- Definitive · ClinGen · X-linked · 2018
- Definitive · G2P · X-linked · 2015
- Strong · Labcorp Genetics (formerly Invitae) · X-linked · 2022
- Strong · PanelApp Australia · X-linked · 2025
- Supportive · Orphanet · X-linked · 2021
Where it sits
Other names
7 names
Resolves to: Allan-Herndon-Dudley syndrome
- Also called
- AHDSALLAN-Herndon syndromeMCT8 deficiencyMCT8-specific thyroid hormone cell Membrane transporter deficiencyMCT8-Specific Thyroid Hormone Cell Transporter Deficiencymonocarboxylate transporter 8 deficiencyX-linked intellectual disability-hypotonia syndrome