The syndromes described by Kanner and Rett-Hagberg: overlap in an extended family.

An extended family is reported in which Rett-Hagberg syndrome, autism with mild ataxia and autism with profound mental retardation occurred separately in three female second-cousins. The authors suggest alternative explanations for the possible association between autism and Rett-Hagberg syndrome: that they may be closely related genetic disorders, or that they may constitute relatively homogeneous phenotypes with several possible aetiologies.