Is DPYD p.Arg78Ter (c.232A>T) pathogenic?

DPYD p.Arg78Ter (c.232A>T) is classified Likely pathogenic in DPYD (ClinVar, No assertion criteria, 1 submitter; last evaluated 2015-12-28). Very rare (popmax 0.00133%, afr); Associated with dihydropyrimidine dehydrogenase deficiency.

What condition is associated with DPYD p.Arg78Ter (c.232A>T)?

DPYD p.Arg78Ter (c.232A>T) is associated with dihydropyrimidine dehydrogenase deficiency (ClinVar).

How common is DPYD p.Arg78Ter (c.232A>T) in the general population?

DPYD p.Arg78Ter (c.232A>T) is very rare (popmax 0.00133%, afr) (gnomAD).

How is Dihydropyrimidine dehydrogenase deficiency inherited?

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

DPYD p.Arg78Ter

c.232A>T · rs776692894 · VCV370260

Likely pathogenic No assertion criteria

Classification

Likely pathogenic

ClinVar

Review

No assertion criteria ☆☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.00133%, afr)

Conditions

dihydropyrimidine dehydrogenase deficiency

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function
NMD	predicted	premature termination codon in exon 3 of 23
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 6.2	GERP 1.9, phastCons 1
Overall
CADD	44.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00133% African / African-American · 1/75,028 alleles

Filtering AF 7.9e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 5.4e-05%

Overall 0.000342% 5/1,461,320 alleles · very rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00133%	75,028
European (non-Finnish)	0.000339%	294,930

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: DPYD
Protein: p.Arg78Ter
Coding: c.232A>T
MANE Select: NM_000110
dbSNP: rs776692894
Type: single nucleotide variant
Location: chr1:97828115 (GRCh38)
Gene constraint: LOEUF 1.09 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 96.23
Residue 78: the 4fe-4s ferredoxin-type 1 domain

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

Disease context

dihydropyrimidine dehydrogenase deficiency — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Dihydropyrimidine dehydrogenase deficiency (Orphanet):

Inheritance: Autosomal recessive
Onset: All ages

Similar variants

DPYD c.1340-2A>C Likely pathogenic ★★ same condition
DPYD c.1905+1G>C Pathogenic/Likely pathogenic ★★ same condition
DPYD c.233+1G>T Likely pathogenic ★★ same condition
DPYD c.2622+1G>A Likely pathogenic ★★ same condition
DPYD c.2767-1G>A Likely pathogenic ★★ same condition
DPYD c.680+1G>T Likely pathogenic ★★ same condition
DPYD p.Arg21Ter Pathogenic/Likely pathogenic ★★ same condition
DPYD p.Arg561Ter 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/dpyd-p-arg78ter (accessed [today's date]).

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