THOC2 and Intellectual disability: In addition to FAM50A, recent studies have highlighted intellectual disability and craniofacial characteristics in patients with defects in the components of spliceosome complex: EFTUD2 mutations cause Guion-Almeidatype mandibulofacial dysostosis; EIF4A3 variants cause Richieri–Costa–Pereira syndrome; THOC2 variants result in an intellectual disability and abnormal gait (Lee et al., 2020).