Central nervous system (CNS) developmental anomalies are hallmark features of MFDM,[33] with congenital microcephaly indicating prenatal origin of cerebral malformations.[6, 9, 34] Pathogenic missense mutations in EFTUD2 have been identified as loss‐of‐function variants (Figure 1), and together with clinically reported nonsense and frameshift mutations, these findings strongly suggest that EFTUD2 contributes to MFDM through a loss‐of‐function mechanism. This evidence concerns the gene EFTUD2 and microcephaly.