Is FTCD p.Arg350= (c.1050C>G) pathogenic?

FTCD p.Arg350= (c.1050C>G) is classified Benign in FTCD (ClinVar, Multiple submitters, 2 submitters; last evaluated 2026-01-26). Common (popmax 12.6%, afr) — too common for a highly-penetrant pathogenic allele; Associated with formiminoglutamic aciduria.

What condition is associated with FTCD p.Arg350= (c.1050C>G)?

FTCD p.Arg350= (c.1050C>G) is associated with formiminoglutamic aciduria (ClinVar).

How is Formiminoglutamic aciduria inherited?

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

FTCD p.Arg350=

Q: How common is FTCD p.Arg350= (c.1050C>G) in the general population?

FTCD p.Arg350= (c.1050C>G) is common (popmax 12.6%, afr) — too common for a highly-penetrant pathogenic allele (gnomAD).

c.1050C>G · rs138803850 · VCV340426

Benign Multiple submitters

Classification

Benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

gnomAD v4.1

Common

common (popmax 12.6%, afr) — too common for a highly-penetrant pathogenic allele

Conditions

formiminoglutamic aciduria

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 1.4	GERP -2.1, phastCons 1
Overall
CADD	5.898	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 12.6% African / African-American · 5,458/43,454 alleles

Filtering AF 12.3% ClinGen BA1/BS1 input FAF95, joint · FAF99 12.2%

Overall 0.519% 6,623/1,276,756 alleles · common exomes 3,326/1,208,274 · genomes 3,297/68,482 · joint denominator

Ancestry group	Frequency	1 in
African / African-Americangrpmax	12.6%	8
Admixed American	1.35%	74
Remaining individualsnot grpmax-eligible	0.81%	123
Middle Eastern	0.442%	226
European (non-Finnish)	0.0363%	2,754
South Asian	0.0146%	6,844

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.Arg350=
Coding: c.1050C>G
MANE Select: NM_206965
dbSNP: rs138803850
Type: single nucleotide variant
Location: chr21:46145866 (GRCh38)
Gene constraint: LOEUF 1.61 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 95.30
Residue 350: 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-arg350 (accessed [today's date]).

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