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Condition report · Endocrine

Thyroid Hormone Resistance

Inherited conditions in which thyroid hormone cannot act, enter cells or be processed normally, caused by variants in THRB, THRA, SLC16A2 (MCT8) or SECISBP2. Blood thyroid tests can look abnormal in unusual ways.

A condition report looks for rare variants known to cause the conditions it covers.

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The 4 conditions we analyse

Resistance to thyroid hormone beta (THRB)

Reduced response to thyroid hormone, with raised thyroid hormone levels and normal or raised TSH; often mistaken for an overactive thyroid.

What a diagnosis changes

Recognising it avoids unnecessary antithyroid drugs, radioiodine or thyroid surgery.

Genes analysed

Includes 3 related subtypes ↓
  • selective pituitary resistance to thyroid hormone
  • thyroid hormone resistance, generalized, autosomal dominant
  • thyroid hormone resistance, generalized, autosomal recessive
MONDO:0700478Orphanet 566243

Resistance to thyroid hormone alpha (THRA)

Autosomal dominant

Reduced thyroid hormone action in tissues with near-normal thyroid tests, causing growth delay, constipation and developmental features.

What a diagnosis changes

Levothyroxine can improve some features.

Also known as

resistance to thyroid hormone alpha

MONDO:0034216Orphanet 566231MedGen 1830097

Allan-Herndon-Dudley syndrome (MCT8 deficiency)

X-linked recessive

A disorder of thyroid hormone transport into the brain, causing severe developmental disability in boys with high T3 levels.

What a diagnosis changes

Tiratricol is approved in some regions to treat the effects of high thyroid hormone in the body.

Genes analysed

Also known as

AHDS; ALLAN-Herndon syndrome; intellectual disability and muscular atrophy; MCT8 deficiency; MCT8-specific thyroid hormone cell Membrane transporter deficiency; MCT8-Specific Thyroid Hormone Cell Transporter Deficiency; mental retardation and muscular atrophy; mental retardation, X-linked, with hypotonia; monocarboxylate transporter 8 deficiency; T3 resisitence; triiodothyronine resistance; X-linked intellectual disability with hypotonia; X-linked intellectual disability-hypotonia syndrome

MONDO:0010354OMIM 300523Orphanet 59MedGen 208645

SECISBP2-related abnormal thyroid hormone metabolism

Autosomal recessive

A defect in selenoprotein production that disturbs thyroid hormone processing, with high T4, low T3 and other features.

Genes analysed

Also known as

short stature-delayed bone age due to thyroid hormone metabolism deficiency; THMA1; thyroid hormone metabolism, abnormal

MONDO:0800046OMIM 609698Orphanet 171706MedGen 1801974

Other endocrine conditions

All conditions →

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