HMOX2

Chr 16

heme oxygenase 2

Also known as: HO-2

Heme oxygenase-2 catalyzes the oxidative cleavage of heme to generate biliverdin, carbon monoxide, and iron, serving as the constitutive isoform of this essential heme catabolism enzyme. Mutations in HMOX2 cause autosomal recessive heme oxygenase-2 deficiency, a rare disorder affecting heme metabolism. The gene shows low constraint against loss-of-function variants, consistent with its recessive inheritance pattern.

OMIMResearchSummary from RefSeq, UniProt
DNmechanismLOEUF 0.97
Clinical SummaryHMOX2
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
0.97LOEUF
pLI 0.000
Z-score 1.67
OE 0.54 (0.310.97)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
0.11Z-score
OE missense 0.98 (0.861.10)
182 obs / 186.3 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.54 (0.310.97)
00.351.4
Missense OE0.98 (0.861.10)
00.61.4
Synonymous OE1.03
01.21.6
LoF obs/exp: 8 / 15.0Missense obs/exp: 182 / 186.3Syn Z: -0.19
DN
0.6259th %ile
GOF
0.6247th %ile
LOF
0.2484th %ile

The Badonyi & Marsh model scores gain-of-function highest, but genomic evidence most strongly supports dominant-negative as the primary mechanism.

DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

HMOX2 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →