Microsatellite DNA assays reveal an allelic imbalance in p16(Ink4), GALT, p53, and APOA2 loci in patients with endometriosis

Objective: To detect allelic imbalance on specific genetic loci occurring i n endometriosis. Design: Microsatellite analysis. Setting: Paraffin-embedded tissues histologically confirmed as endometrioti c or normal endometrium. Patient(s): Premenopausal women undergoing laparoscopy for suspected endome triosis. Intervention(s): Laparoscopic excision of specimens. Main Outcome Measure(s): Allelic imbalance and alterations of intensity of microsatellite alleles. Result(s): Five of 17 microsatellite DNA markers (29.4%) showed allelic imb alance. Eight samples (36.4%) showed allelic imbalance in at least one locu s. Loci 9p21, 1q21, and 17p13.1 exhibited imbalance in 27.3%, 4.5%, and 4.5 %, respectively. A 3-fold increase of the fractional allelic loss was obser ved from disease stage II to III and IV, whereas only 1.3-fold was found be tween patients of 41-50 and 20-40 years. Conclusion(s): We found that loss of heterozygosity on p16(Ink4), GALT, and p53, as well as on APOA2, a region frequently lost in ovarian cancer, occu rs in endometriosis, even in stage II of the disease. The occurrence of suc h genomic alterations may represent important events in the development of endometriosis. The 9p21 locus may contain a gene associated with the pathog enesis of the disease, and therefore its loss may be a prognostic marker of the disease. (C) 2001 by American Society for Reproductive Medicine.