Biallelic loss of function variants in COASY cause prenatal onset pontocerebellar hypoplasia, microcephaly, and arthrogryposis

Tessa van Dijk, Sacha Ferdinandusse, Jos P N Ruiter, Mariëlle Alders, Inge B Mathijssen, Jillian S Parboosingh, A Micheil Innes, Hanne Meijers-Heijboer, Bwee Tien Poll-The, Francois P Bernier, Ronald J A Wanders, Ryan E Lamont, Frank Baas

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Pontocerebellar hypoplasia (PCH) is a heterogeneous neurodegenerative disorder with a prenatal onset. Using whole-exome sequencing, we identified variants in the gene Coenzyme A (CoA) synthase (COASY) gene, an enzyme essential in CoA synthesis, in four individuals from two families with PCH, prenatal onset microcephaly, and arthrogryposis. In family 1, compound heterozygous variants were identified in COASY: c.[1549_1550delAG]; [1486-3 C>G]. In family 2, all three affected siblings were homozygous for the c.1486-3 C>G variant. In both families, the variants segregated with the phenotype. RNA analysis showed that the c.1486-3 C>G variant leads to skipping of exon 7 with partial retention of intron 7, disturbing the reading frame and resulting in a premature stop codon (p.(Ala496Ilefs*20)). No CoA synthase protein was detected in patient cells by immunoblot analysis and CoA synthase activity was virtually absent. Partial CoA synthase defects were previously described as a cause of COASY Protein-Associated Neurodegeneration (CoPAN), a type of Neurodegeneration and Brain Iron Accumulation (NBIA). Here we demonstrate that near complete loss of function variants in COASY are associated with lethal PCH and arthrogryposis.

Original languageEnglish
Pages (from-to)1752-1758
Number of pages7
JournalEuropean Journal of Human Genetics
Volume26
Issue number12
Early online date8 Aug 2018
DOIs
Publication statusPublished - 1 Dec 2018

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