Novel COL4A2 mutation causing familial malformations of cortical development

This article aimed to describe a novel COL4A2 mutation and the phenotypic features of two family members presenting with epilepsy and cortical development malformations.

The first patient is a 65-year-old woman with hematuria and adult-onset seizures. Brain MRI showed closed lip schizencephaly of right lateral sulcus associated with polymicrogyria of the surrounding cortex and areas of subcortical heterotopia. The second patient is a 40-year-old man, her son. He was born post-term with neonatal distress and psychomotor developmental delay with congenital left leg paresis and strabismus, as well as childhood-onset focal motor seizures. Brain MRI showed a right nucleus-capsular porencephalic cavitation with enlargement of the homolateral ventricle and a focal right occipital cortico-subcortical encephalomalacia. A small heterotopic band was also present in the frontal left subcortical region.

We tested both patients with a NGS panel for genetic epilepsies, which evidenced a missense mutation in COL4A2 gene (c.2972G>A, causing the aminoacidic substitution Gly991Glu).

The phenotypic spectrum associated with COL4A2 mutations has not been extensively described in the literature. Testing for COL4A mutations is indicated in patients with malformations of cortical development, particularly in the presence of familial conditions, even in the absence of porencephaly or early hemorrhagic strokes.