Angiopathie héréditaire avec néphropathie, anévrismes et crampes musculaires (Ahnac) : une nouvelle maladie des membranes basales associée à des mutations du gène COL4A1 (gène codant pour la chaîne α1 du collagène de type IV)

Abstract

Since 2005, several neurological diseases, including porencephaly, leukoencephalopathy and intracerebral hemorrhage without hypertension, and retinal arteriolar tortuosity have been linked to mutations in the COL4A1 gene, which encodes the alpha1 chain of type IV collagen, the main constituent of basement membranes. In three families, we observed a new syndrome that we called HANAC, for hereditary angiopathy with nephropathy, aneurysms and muscle cramps, which is associated with morphological alterations of cutaneous and renal basement membranes. This novel "basalopathy" is caused by glycine mutations in COL4A1 exons 24 and 25. We discuss phenotype-genotype correlations and the implications of the HANAC syndrome for the diagnosis of autosomal dominant hematuria, cystic kidney disease, intracranial aneurysms, and muscle cramps.