Chromosome 22q duplication syndrome. 22q+ syndrome. Trisomy 22q.
Incidence
Very rare syndrome. Sporadic.
Clinical Characteristics
Duplication of the long arm of chromosome 22. Clinical characteristics vary with the karyotype and may include craniofacial, ocular, and genital abnormalities and developmental delay. 22q duplication is associated with two distinct syndromes, Cat eye syndrome and derivative 22 (der 22) syndrome. Der 22 has a larger duplication at proximal chromosome 22 than cat eye syndrome and is seen in offspring of balanced carriers of the 11;22 translocation and is due to a 3;1 malsegregation which results in partial duplication of proximal long arm of chromosome 22 and of distal long arm of chromosome 11.
Precipitants
None
Provocation Tests
None
Diagnostic Procedures
Karyotype. Duplication of the long arm of chromosome 22.