IDH3G
Chr XXLRisocitrate dehydrogenase (NAD(+)) 3 non-catalytic subunit gamma
Also known as: H-IDHG, RP99
The protein is the gamma subunit of NAD(+)-dependent isocitrate dehydrogenase, which catalyzes the rate-limiting step of the tricarboxylic acid cycle by decarboxylating isocitrate to alpha-ketoglutarate in the mitochondrial matrix. Mutations cause retinitis pigmentosa 99, inherited in an X-linked recessive pattern. The pathogenic mechanism appears to be dominant-negative, where mutant protein disrupts the normal function of the heterotetrameric enzyme complex.
Primary Disease Associations & Inheritance
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Typical tolerance to LoF variation
Moderately missense-constrained (top ~2.5%)
The highest-scoring mechanism for this gene is dominant-negative.
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
IDH3G · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
No active trials found for this gene.
Search ClinicalTrials.gov →External Resources
Links to major genomics databases and tools