Loss of heterozygosity on chromosomes 1p and 11p in sporadic pheochromocytoma.

We used 29 polymorphic DNA markers to analyze tumor DNA samples from six patients with sporadic pheochromocytoma for possible loss of chromosomal heterozygosity; four had benign disease and two had malignant disease. Loss of heterozygosity was observed on four chromosomes: 1p (three of four patients), 2p (one of one), 5q (two of six), and 11p (three of five). Chromosomes 1p and 11p frequently had allelic deletions in these tumors, and these deletions may play an important role in the development of pheochromocytoma.