Length polymorphism in the pro alpha 2(I) collagen gene: an alternative explanation in a case of Marfan syndrome.

A 38 base pair (bp) insertion in the pro alpha 2(I) collagen gene (COL1A2) of a patient with Marfan syndrome has been proposed to be the possible cause of the disease (Henke et al. 1985). However, analysis of this insertion in DNA from the patient in question and from random normal individuals reveals it to be a common polymorphism. We suggest that the 38 bp insertion is not related to the primary defect in this case of Marfan syndrome.