RFX5
Chr 1ARregulatory factor X5
Also known as: MHC2D3, MHC2D5
RFX5 encodes the 75-kD subunit of RFX, a nuclear protein complex that activates transcription from MHC class II promoters by binding to X-boxes in the promoter regions. Mutations cause MHC class II deficiency (bare lymphocyte syndrome), an autosomal recessive severe combined immunodeficiency presenting in early infancy with recurrent infections due to absent MHC class II expression on immune cells. The gene shows very low constraint against loss-of-function variants (pLI near zero), consistent with its recessive inheritance pattern.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Mild missense constraint
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
RFX5 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
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