We add two novel variants to the existing mutation spectrum of ASNS gene. Loss of ASNS function should be suspected in newborns presenting with congenital microcephaly, intellectual disability, progressive cerebral atrophy, and intractable seizures. Acquisition and sequencing of stored newborn blood spot can be a valuable option when no biological samples are available from a deceased child.
Keywords: Archived newborn blood spot; asparagine synthetase; asparagine synthetase deficiency; dried blood spot; whole exome sequencing.