title: Phenotypic variation in two patients with a ring chromosome 22.
abstract: Two severely mentally retarded patients with a ring chromosome 22 presented with disparate phenotypes: one patient manifested only minimal dysmorphic features, whereas the other had a distinctive pattern of anomalies consisting of an abnormal skull configuration with mild maxillary hypoplasia, a large nose, thick full lips, a protruding tongue, lymphedema, hypotonia and an unsteady gait. The findings in these and previously reported patients indicate that a ring chromosome 22 is usually associated with moderate to severe mental retardation, with a range of dysplastic features from mild and nonspecific to more marked and distinctive.
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics; D000293:Adolescent; D002869:Chromosome Aberrations; D002904:Chromosomes, Human, 21-22 and Y; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*