Is HPD p.Gly140= (c.420G>A) pathogenic?

HPD p.Gly140= (c.420G>A) is classified Likely benign in HPD (ClinVar, Single submitter, 1 submitter; last evaluated 2023-02-15). Very rare (popmax 0.00017%, nfe); Associated with hawkinsinuria.

What condition is associated with HPD p.Gly140= (c.420G>A)?

HPD p.Gly140= (c.420G>A) is associated with hawkinsinuria, tyrosinemia type III (ClinVar).

How common is HPD p.Gly140= (c.420G>A) in the general population?

HPD p.Gly140= (c.420G>A) is very rare (popmax 0.00017%, nfe) (gnomAD).

How is Hawkinsinuria inherited?

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

HPD p.Gly140=

c.420G>A · rs770777067 · VCV2923964

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00017%, nfe)

Conditions

hawkinsinuria

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 -1.7	GERP -2.4
Overall
CADD	1.821	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00017% European (non-Finnish) · 2/1,177,944 alleles

Filtering AF 2.8e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 1.1e-05%

Overall 0.000137% 2/1,459,250 alleles · very rare

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: HPD
Protein: p.Gly140=
Coding: c.420G>A
MANE Select: NM_002150
dbSNP: rs770777067
Type: single nucleotide variant
Location: chr12:121849785 (GRCh38)
Gene constraint: LOEUF 0.845 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 96.00 · 4 PDB
Residue 140: the voc 1 domain

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

Disease context

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

Also linked: tyrosinemia type III

For Hawkinsinuria (Orphanet):

Inheritance: Autosomal dominant
Onset: Infancy, Neonatal
Prevalence: <1 / 1 000 000 (Worldwide)

Similar variants

HPD p.Arg225Ter Pathogenic/Likely pathogenic ★★ same condition
HPD p.Gln205Ter Pathogenic/Likely pathogenic ★★ same condition
HPD p.Tyr160Cys Likely pathogenic ★★ same condition
HPD p.Ala230Thr Uncertain significance ★★ ⚠ same condition
HPD p.Arg111Trp Uncertain significance ★★ ⚠ same condition
HPD p.Arg119Gln Uncertain significance ★★ ⚠ same condition
HPD p.Arg279Gly Uncertain significance ★★ ⚠ same condition
HPD p.Arg300Trp 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/hpd-p-gly140 (accessed [today's date]).

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