Evidence of the milder phenotypic spectrum of c.1582G>A PIGT variant: Delineation based on seven novel Polish patients

Abstract

PIGT is one of over 29 glycosylphosphatidylinositol biosynthesis defect genes. Mutations cause genetically determined disorders characterized mainly by epilepsy with fever-sensitivity, central hypotonia, psychomotor delay and congenital malformations. The disease is known as multiple congenital anomalies-hypotonia-seizures syndrome 3 (MCAHS3) or glycosylphosphatidylinositol biosynthesis defect-7. Twenty-eight cases have been reported until today. We present seven novel Polish patients, all harboring 1582G>A variant in a homozygous or compound heterozygous state which seems to cause a milder phenotype of the disease.

Keywords: PIGT gene; antiepileptic drugs; developmental encephalopathy with epilepsy; fever-associated epilepsy; glycosylphosphatidylinositol biosynthesis defects.