CPSF3 and syndromic intellectual disability: Taken together, the crucial biological function of CPSF3 in humans, the prior evidence from animal models, and the consistency of the phenotype among the six confirmed homozygous patients, all support the role of the two CPSF3 variants, p.Gly468Glu and p.Ile354Thr, in the intellectual disability syndrome observed among homozygous carrier patients.