Prenatal diagnosis of dominant dystrophic epidermolysis bullosa, by COL7A1molecular analysis

Wa report the first direct molecular prenatal diagnosis, undertaken for the autosomal dominant form of dystrophic epidermolysis bullosa (DDEB). The pr oband had a moderately severe form of DDEB, with episodic blistering of ski n and mucosal involvement. Diagnostic histopathological examination, using electron microscopy to evaluate skin from a fresh blister, demonstrated a z one of cleavage beneath the epidermal-dermal junction, thereby assigning th e EB as dystrophic. DNA analysis of COL7A1, the gene encoding type VII coll agen, identified a heterozygous transversion (G to A) in the triple helix d omain (G2043R). For any subsequent pregnancy, the affected mother and the u naffected father of the proband requested prenatal prediction, which was th ereafter carried out in DNA extracted from a chorionic villus sample obtain ed at 11 weeks of gestation. Restriction enzyme analysis of COL7A1 exons 73 and 74 amplified by PCR, demonstrated the presence of the C2043R mutation, and the pregnancy was subsequently terminated. Molecular analysis of DNA e xtracted from fetal tissues confirmed the prenatal prediction. Copyright (C ) 2000 John Wiley & Sons, Ltd.