MMADHC (Q9H3L0) variants and mutations

MMADHC (also known as Q9H3L0) is a human protein-coding gene encoding a cobalamin trafficking protein CblD protein. It directs intracellular cobalamin toward the methylcobalamin and adenosylcobalamin pathways needed for methionine and methylmalonyl-CoA metabolism. Biallelic pathogenic variants cause cblD disease, producing isolated or combined methylmalonic acidemia and homocystinuria. This analysis covers 595 MMADHC variants and mutations. Of these, 79% have computational variant effect predictions. Disease context includes methylmalonic aciduria and homocystinuria type cblD, Methylmalonic acidemia with homocystinuria, type cblD, and Methylmalonic acidemia with homocystinuria. Example MMADHC variants include A2T, A2V, and N3=.

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, MaveDB, LitVar.

Notable MMADHC variants

Examples include A2T, A2V, N3=, N3D, N3H, N3K, N3S, V4M. Listed records include available protein-change notation, database identifiers, clinical classifications, computational predictions, population evidence, experimental measurements, and disease context.