MFSD2A and microcephaly: The MFSD2A gene, expressed in oligodendrocyte precursor cells, is essential for lysophosphatidylcholine uptake during myelination.62 MFSD2A-deficient mice are characterized by neuronal cell loss in the hippocampus and cerebellum, as well as cognitive deficits, severe anxiety and microcephaly.63 The SLC1A4 gene, a sodium-dependent neutral amino acid transporter, is highly expressed in many tissues, including the brain, primarily in astrocytes.