Down syndrome and associated congenital malformations

Congenital malformations are many times more common in individuals with Down syndrome (DS) than in the general population. The scope of these defects is as broad in DS as it is in the general population. A positive correlation exists between the prevalence of these defects in both groups, but the incidence of each is many times greater in DS. Two examples, Brushfield spots and anorectal abnormalities are noted in which racial/ethnic prevalence differences exist. The incidence of each condition in the subpopulation with DS is proportional to but many times greater than the incidence of that condition in the general population from which the subpopulation with DS was derived. Findings presented in this review support the notion that the autosomal trisomic state amplifies expression of exposure to teratogens.