Renal Macrocystic Disease
Gene: COL4A4
Discussion with KidGen renal experts (Andrew Mallett and Amali Mallawaarchchi): causative relationship with cystic kidney disease not well established; some conflicting literature. Variants need to be interpreted with caution in the setting of cystic kidney disease (as relatively common in the general population): especially so in relatively young patients (<40yo) with normal GFR and in patients with otherwise typical ADPKD findings (more likely to have missed PKD1/PKD2 variant).Created: 24 Mar 2025, 1:49 a.m. | Last Modified: 24 Mar 2025, 1:49 a.m.
Panel Version: 0.80
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Multiple kidney cysts, usually with normal kidney volume, were found in 37% (26/70) of patients with a genetically confirmed AS (COL4A3-5), mostly ADAS. A few patients' kidney volumes were similar to autosomal dominant polycystic kidney disease. The prevalence of cystic kidney phenotype was significantly higher in patients with AS compared to those with IgA nephropathy (42% vs 19%; P=0.002). The cystic phenotype in the AS patients was associated with an older age and lower eGFR levels.
Sources: LiteratureCreated: 11 Dec 2024, 1:24 a.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Alport syndrome MONDO:0018965
Publications
Variants in this GENE are reported as part of current diagnostic practice
Gene: col4a4 has been classified as Amber List (Moderate Evidence).
Gene: col4a4 has been classified as Green List (High Evidence).
Gene: col4a4 has been classified as Green List (High Evidence).
gene: COL4A4 was added gene: COL4A4 was added to Renal Macrocystic Disease. Sources: Literature Mode of inheritance for gene: COL4A4 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for gene: COL4A4 were set to 38514012 Phenotypes for gene: COL4A4 were set to Alport syndrome MONDO:0018965 Review for gene: COL4A4 was set to GREEN gene: COL4A4 was marked as current diagnostic