ABSTRACT
Marfan syndrome is a systemic disorder o f connective tissue with autosomal dominant inheritance and a prevalence of approximately 1 in 10,000 individ uals. It is estimated that between 15 and 25% of cases occur in the absence of a family history, presumed new mutations due to parental germ line defects (1). There are no documented examples o f skipped generations (high pene trance), but marked interfamilial-and, to a lesser extent, intrafamilial-vari ability in the distribution and severity o f tissue involvement is the rule. The lack o f a sensitive or specific genetic or biochemical test for the disorder, compounded by a high rate o f new mutation and marked clinical variability, has frustrated the accurate diagnosis o f equivocal cases and may have perpet uated an underestimation o f disease prevalence.
