Trisomy 22 with 'cat eye' anomaly.

The case of a 10-month-old girl with an extra G-like chromosome is presented. Quinacrine, trypsin-Giemsa, and reverse banding identified the extra chromosome as no. 22. The phenotype of the patient is unique in that unilateral iris coloboma was observed, unlike the 18 cases of full trisomy 22 already published. This represents the first reported case of full trisomy 22 with this coloboma, or 'cat eye' anomaly, which is usually associated with partial trisomy 22. It is suggested that the use of the term 'cat eye syndrome' be revised. The terms 'partial trisomy 22 syndrome' and 'trisomy 22 syndrome' should be used instead.