COL4A4
Chr 2ARADcollagen type IV alpha 4 chain
Also known as: ATS2, BFH, BFH1, CA44
The protein forms part of type IV collagen, the major structural component of glomerular basement membranes where it creates a meshwork with other proteins. Mutations cause autosomal recessive Alport syndrome type 2 (hereditary glomerulonephropathy) and autosomal dominant familial benign hematuria (thin basement membrane disease), both primarily affecting kidney function. This gene is highly constrained against loss-of-function variants, indicating its critical importance for normal development and function.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Typical tolerance to LoF variation
Mild missense constraint
Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.
The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
COL4A4 · 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
Safety and Efficacy of ACEI in Alport Syndrome Patients With COL4A3/COL4A4/COL4A5 Variants
NOT YET RECRUITINGThe Collagen Factors of Rapid Progression of Keratoconus in Children.
RECRUITINGBAY3401016; Biomarker Study Alport
RECRUITINGGenotype-Phenotype Correlations in Patients With Alport Syndrome
RECRUITINGExternal Resources
Links to major genomics databases and tools