Phosphoserine aminotransferase deficiency: imaging findings in a child with congenital microcephaly

Serine deficiency disorders can result from deficiency in one of three enzymes. Deficiency of the second enzyme, 3-phosphoserine aminotransferase (PSAT), has been reported in two siblings; the eldest investigated for acquired microcephaly, spasticity and epilepsy. Our patient had neurological symptoms at birth. Fetal magnetic resonance imaging (MRI) at 35-week gestation demonstrated microencephaly and gyral simplification (anterior posterior) which was confirmed upon postnatal MRI. Congenital microcephaly was apparent at birth. PSAT deficiency was confirmed when exome sequencing identified biallelic mutations in