Previous studies have identified 27 carriers of 14 mutant Eg5 alleles in 15 independent families and found that Eg5 mutation is a significant proportion of cases of MLCRD (microcephaly, primary lymphedema, and chorioretinal dysplasia) syndrome and CDMMR (chorioretinal dysplasia, microcephaly, and mental retardation) syndrome [19]. The gene discussed is KIF11; the disease is Intellectual disability.