CNTN6 and microcephaly: Studies about CNTN4 (MIM 607280) indicate that it belongs to the same family as CNTN6. In a patient described by Fernandez et al., [22], CNTN4 was disrupted by a balanced translocation, while the patient displayed severe clinical manifestations associated to monosomy 3p (in particular the facial features without triangular face or microcephaly) and mental retardation.