Trisomy 22. Two new cases and delineation of the phenotype

Abstract

Two unrelated children, not affected with Down's syndrome, with strikingly similar phenotypes and an extra G like chromosome are presented. Quinacrine and trypsin Giemsa banding identified the extra chromosome as No.22. The phenotype of these patients and the review of 15 additional similar cases from the literature enable a definition of the cardinal features of trisomy 22: mental and growth retardation, microcephaly and craniofacial asymmetry, strabismus, beaked and prominent nose, long philtrum, cleft palate, micrognathia, large low set ears with preauricular tags and/or pits, long slender fingers, congenital heart disease, inguinal hernia, and hip dislocation.