The 18-Trisomy Syndrome —Two New Clinical Variants

Abstract

THE autosomal trisomy syndrome of numerous congenital anomalies associated with a modal chromosome number of 47, the extra chromosome being either number 17 or 18, is now well established.¹ Rece-t reports^{1 2 3 4} have differed in the identification of the extra autosome, some favoring a designation as, number 18^{1 , 2} and some favoring, number 7.^{3 , 4} Although precise identification is difficult if not impossible, analysis of the idiograms reported below suggested the extra autosome to be number 18. This symptom complex is therefore referred to asromy 18.The sources cited above have agreed, however, on the major systems involved in most of the . . .