CRELD1 and microcephaly: p.(Cys192Tyr) and p.(Gln320Argfs25) are also the two CRELD1 variants with the highest allele counts in gnomAD and were found predominantly in non-Finnish European populations6, further supporting a founder effect.Comparatively, individuals with the p.(Gln320Argfs25) variant in trans with other missense alleles (e.g., p.(Asp386Asn), p.(Cys262Arg), and the novel p.(Gly267Ala) in Patient 3) have not consistently exhibited microcephaly or feeding difficulties, though seizures were universally present.