Arginase catalyzes the hydrolysis of arginine to ornithine and urea. At least two isoforms of mammalian arginase exist (types I and II) which differ in their tissue distribution, subcellular localization, immunologic crossreactivity and physiologic function. The type I isoform encoded by this gene, is a cytosolic enzyme and expressed predominantly in the liver as a component of the urea cycle. Inherited deficiency of this enzyme results in argininemia, an autosomal recessive disorder characterized by hyperammonemia. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2011]

GeneReviewsOMIMResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

ArgininemiaMIM #207800
AR

Clinical highlights

Gene-disease validity (ClinGen)
arginase deficiency · ARDefinitivesufficient evidence for diagnostic panels
Interpreting a novel variant
Loss of function is the curated mechanism (Gene2Phenotype), though the gene is not strongly LoF-constrained in the population — weigh truncating variants against that tolerance.Curated gene-level mechanism — a prior for triage, not a per-variant call.
4
Active trials
633
Pubs (1 yr)
P/LP submissions
P/LP missense
0.92
LOEUF
LOF
Mechanism· G2P
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GeneReview available — ARG1
Authoritative clinical overview · Recommended first read
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Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint?
0.92LOEUF
pLI 0.000
Z-score 1.81
OE 0.51 (0.300.92)
Tolerant

Typical tolerance to LoF variation

Missense Constraint?
0.06Z-score
OE missense 0.99 (0.871.12)
176 obs / 178.1 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.51 (0.300.92)
00.351.4
Missense OE?0.99 (0.871.12)
00.61.4
Synonymous OE?1.00
01.21.6
LoF obs/exp: 8 / 15.7Missense obs/exp: 176 / 178.1Syn Z: 0.01

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

ARG1 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

VCEP specificationsUrea Cycle DisordersReleased
Panel ↗