Is TH p.Phe103Ser (c.308T>C) pathogenic?

TH p.Phe103Ser (c.308T>C) is classified Uncertain significance in TH (ClinVar, Single submitter, 1 submitter; last evaluated 2019-07-09). AlphaMissense: likely pathogenic (0.9494); Absent from gnomAD v4.1; Associated with TH-deficient dopa-responsive dystonia.

What condition is associated with TH p.Phe103Ser (c.308T>C)?

TH p.Phe103Ser (c.308T>C) is associated with TH-deficient dopa-responsive dystonia (ClinVar).

How common is TH p.Phe103Ser (c.308T>C) in the general population?

TH p.Phe103Ser (c.308T>C) is absent from gnomAD v4.1 (gnomAD).

How is Autosomal recessive dopa-responsive dystonia inherited?

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

What do computational predictors say about TH p.Phe103Ser (c.308T>C)?

AlphaMissense predicts likely pathogenic (score 0.9494) — an in-silico prediction, not a clinical call.

TH p.Phe103Ser

c.308T>C · rs2495828134 · VCV2437076

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely pathogenic

0.9494 · ACMG-weighted

gnomAD v4.1

Absent

absent from gnomAD v4.1

Missense predictors

3/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

TH-deficient dopa-responsive dystonia

Computational evidence

Protein change
AlphaMissense	0.9494	likely pathogenic
REVEL	0.792	moderately pathogenic-leaning
SaProt	LLR -12.67	damaging
⇒ AlphaMissense, REVEL and SaProt all call this damaging.
Splicing
SpliceAI	<0.2	all four deltas below 0.2 · A>C here scores Δ0.91 · evaluated, not missing
Constraint at this position
Conservation	phyloP 11	GERP 0.7, phastCons 1
Regional constraint	o/e 1.03	unconstrained · MANE · 7,550 bp · p 0.38 · regional, not allelic
Overall
CADD	25.2	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean damaging — a triage signal, not a reclassification

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

⚠ Isoform check: AlphaMissense numbered on a different transcript (AM F134S vs ClinVar F103S) — verify the residue.

Population frequency

gnomAD v4.1 · exomes + genomes

Absent from gnomAD v4.1. Not observed in any sequenced alleles — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

Variant & gene context

Gene: TH
Protein: p.Phe103Ser
Coding: c.308T>C
MANE Select: NM_000360
dbSNP: rs2495828134
Type: single nucleotide variant
Location: chr11:2169654 (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.Phe103= Likely benign ★ 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-phe103ser (accessed [today's date]).

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