Is FTCD p.Asp434= (c.1302C>T) pathogenic?

FTCD p.Asp434= (c.1302C>T) is classified Likely benign in FTCD (ClinVar, Single submitter, 2 submitters; last evaluated 2024-12-05). Ultra-rare (popmax 0.0713%, eas); Associated with formiminoglutamic aciduria.

What condition is associated with FTCD p.Asp434= (c.1302C>T)?

FTCD p.Asp434= (c.1302C>T) is associated with formiminoglutamic aciduria (ClinVar).

How common is FTCD p.Asp434= (c.1302C>T) in the general population?

FTCD p.Asp434= (c.1302C>T) is ultra-rare (popmax 0.0713%, eas) (gnomAD).

How is Formiminoglutamic aciduria inherited?

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

FTCD p.Asp434=

c.1302C>T · rs566814523 · VCV2705862

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 2 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0713%, eas)

Conditions

formiminoglutamic aciduria

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation/SpliceAI carries the signal.
Splicing
SpliceAI	Δ0.28	donor loss · deltas
Pangolin	Δ0.33	loss · gain 0.00 · agrees with SpliceAI · independent
Constraint at this position
Conservation	phyloP 0.25	GERP -1.9, phastCons 0.82
Overall
CADD	11.59	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0713% East Asian · 32/44,868 alleles

Filtering AF 0.0519% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0452%

Overall 0.00385% 62/1,612,140 alleles · ultra-rare exomes 59/1,459,848 · genomes 3/152,292 · joint denominator

Ancestry group	Frequency	1 in
East Asiangrpmax	0.0713%	1,402
South Asian	0.0209%	4,793
Remaining individualsnot grpmax-eligible	0.0176%	5,677

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: FTCD
Protein: p.Asp434=
Coding: c.1302C>T
MANE Select: NM_206965
dbSNP: rs566814523
Type: single nucleotide variant
Location: chr21:46138882 (GRCh38)
Gene constraint: LOEUF 1.61 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 95.30
Residue 434: the 'cyclodeaminase/cyclohydrolase' region

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

Disease context

formiminoglutamic aciduria — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Formiminoglutamic aciduria (Orphanet):

Inheritance: Autosomal recessive
Onset: Childhood

Similar variants

FTCD p.Arg255Ter Pathogenic ★★ same condition
FTCD p.Arg71Ter Pathogenic/Likely pathogenic ★★ same condition
FTCD p.Leu536Ter Pathogenic/Likely pathogenic ★★ same condition
FTCD p.Ala108Thr Uncertain significance ★★ ⚠ same condition
FTCD p.Ala159Val Uncertain significance ★★ ⚠ same condition
FTCD p.Ala368Val Uncertain significance ★★ ⚠ same condition
FTCD p.Ala418Thr Uncertain significance ★★ ⚠ same condition
FTCD p.Ala455Thr Uncertain significance ★★ ⚠ 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/ftcd-p-asp434 (accessed [today's date]).

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