Is TH p.Thr8= (c.24G>A) pathogenic?

TH p.Thr8= (c.24G>A) is classified Likely benign in TH (ClinVar, Multiple submitters, 3 submitters; last evaluated 2026-01-20). Ultra-rare (popmax 0.022%, sas); Associated with TH-deficient dopa-responsive dystonia.

What condition is associated with TH p.Thr8= (c.24G>A)?

TH p.Thr8= (c.24G>A) is associated with TH-deficient dopa-responsive dystonia (ClinVar).

How common is TH p.Thr8= (c.24G>A) in the general population?

TH p.Thr8= (c.24G>A) is ultra-rare (popmax 0.022%, sas) (gnomAD).

How is Autosomal recessive dopa-responsive dystonia inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

TH p.Thr8=

c.24G>A · rs529205525 · VCV698725

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.022%, sas)

Conditions

TH-deficient dopa-responsive dystonia

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -14	GERP -1.8
Overall
CADD	1.154	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.022% South Asian · 20/91,056 alleles

Filtering AF 0.0145% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0121%

Overall 0.0031% 50/1,612,508 alleles · ultra-rare exomes 43/1,460,238 · genomes 7/152,270 · joint denominator

Ancestry group	Frequency	1 in
South Asiangrpmax	0.022%	4,553
African / African-American	0.012%	8,336
East Asian	0.00669%	14,953
Remaining individualsnot grpmax-eligible	0.0016%	62,464
European (non-Finnish)	0.00144%	69,400

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: TH
Protein: p.Thr8=
Coding: c.24G>A
MANE Select: NM_000360
dbSNP: rs529205525
Type: single nucleotide variant
Location: chr11:2171763 (GRCh38)
Gene constraint: LOEUF 1.27 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 81.75 · 7 PDB

Full TH gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

TH-deficient dopa-responsive dystonia — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Autosomal recessive dopa-responsive dystonia (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy, Neonatal

Similar variants

TH p.Thr8Met Uncertain significance ★★ ⚠ same residue
TH c.1200+2T>C Likely pathogenic ★★ same condition
TH c.1334+1G>A Likely pathogenic ★★ same condition
TH c.312+1G>A Likely pathogenic ★★ same condition
TH c.488-1G>A Pathogenic ★★ same condition
TH c.644+1G>A Likely pathogenic ★★ same condition
TH c.695+1G>C Likely pathogenic ★★ same condition
TH c.90+10C>T Pathogenic/Likely pathogenic ★★ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/th-p-thr8 (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown