Preclinical diagnosis of pseudoxanthoma elasticum - methodological restrictions and ethical problems.

Pseudoxanthoma elasticum (PXE) is an inherited connective tissue disease. Only recently, mutations in the MRP6 gene on chromosome 16p13.1 have been identified in PXE families. Up to now, predictive testing has not been available. Since ultrastructural connective tissue alterations in overtly normal skin of predilection sites have supported preclinical diagnosis in children of affected individuals, we have screened the daughters of a PXE patient for these alterations. The patient's biopsy from lesional skin revealed elastin and collagen fibril abnormalities, but biopsies from the clinically inconspicuous daughters showed only ultrastructural alterations of collagen fibrils. These findings are inconclusive regarding the diagnosis of PXE in the daughters. Predictive or preclinical diagnosis of incurable, late-onset disorders creates complex social, ethical, and legal problems which call for special management strategies.