HMBS (Porphobilinogen deaminase) variants and mutations

HMBS (also known as Porphobilinogen deaminase) is a human protein-coding gene encoding a porphobilinogen deaminase protein. An enzyme in heme biosynthesis that joins four porphobilinogen molecules to form hydroxymethylbilane. This step is required to build the tetrapyrrole framework of heme, and HMBS dysfunction causes acute intermittent porphyria. This analysis covers 556 HMBS variants and mutations. Of these, 97% have computational variant effect predictions. Disease context includes acute intermittent porphyria, encephalopathy, porphyria-related, and leukoencephalopathy, porphyria-related. Example HMBS variants include M1V, S2P, and S2A.

Variant analysis overview

Variant and mutation evidence

Clinical, disease, and population context

Protein structure and variant hotspots

Data sources

Evidence in this analysis draws on EBI Proteins Variation, UniProt, gnomAD v4, EuropePMC, 3D Hotspot Analysis, Interaction Network Analysis, Protein Data Bank, AlphaFold DB, gnomAD constraint, Open Targets, ClinGen, PharmGKB, MaveDB, LitVar.

Notable HMBS variants

Examples include M1V, S2P, S2A, S2F, S2Y, S2S, G3S, G3V. Listed records include available protein-change notation, database identifiers, clinical classifications, computational predictions, population evidence, experimental measurements, and disease context.