Rare genetic causes of primary microcephaly in two Saudi families identified via whole-exome sequencing: Genomic and phenotypic delineation of pathogenic CDK5RAP2 and CIT variants

variant (MCPH17) was associated with microcephaly, lissencephaly, neonatal seizures, and developmental delays. The patient had a deceased sibling with multiple congenital anomalies, demonstrating the intrafamilial variability of MCPH17. Overall, this study expands the clinical spectrum of MCPH3 and MCPH17; includes the first reported case of TEF in MCPH3; elucidates the ultra-rare clinical manifestation of neonatal seizures in MCPH17; and underscores the utility of WES in early diagnosis of genetically heterogeneous neurodevelopmental conditions. The findings can facilitate the necessary clinical management and counseling.