Further refinement of COL4A1 and COL4A2 related cortical malformations.
Cavallin M, Mine M, Philbert M, Boddaert N, Lepage JM, Coste T, Lopez-Gonzalez V, Sanchez-Soler MJ, Ballesta-Martínez MJ, Remerand G, Pasquier L, Guët A, Chelly J, Lascelles K, Prieto-Morin C, Kossorotoff M, Tournier Lasserve E, Bahi-Buisson N.
Source : Eur J Med Genet
2019 Feb 22
Pmid : 30315939
METHODS: We screened for COL4A1/A2 mutations in 9 patients with schizencephaly and/or polymicrogyria suspected to be caused by vascular disruption and leading to a cerebral haemorrhagic ischaemic event. These included 6 cases with asymmetrical or unilateral schizencephaly and/or polymicrogyria and 3 cases with bilateral schizencephaly.
RESULTS: One de novo missense COL4A1 mutation (c.3715 G > A, p.(Gly1239Arg)) and two COL4A2 mutations were found, respectively in one familial case (c.4129G > A, p.(Gly1377Arg)) and one sporadic patient (c.1776+1G > A). In three other cases, COL4A1 variants of unknown significance were identified. None of our patients demonstrated neuromuscular or hematological anomalies. Brain malformations included a combination of schizencephaly, mainly asymmetrical, with porencephaly or ventriculomegaly (3/3 mutated patients). We did not observe microbleeds or microcalcifications in any of our cases, hence we do not believe that they represent a distinctive feature of COL4A1/A2 mutations.
CONCLUSIONS: Our study further emphasizes the need to search for both COL4A1 and COL4A2 mutations in children presenting with uni- or bilateral polymicrogyria with schizencephaly, even in the absence of intracranial microbleeds, calcification or associated systemic features.