DETECTION OF CHROMOSOMAL ANEUPLOIDY IN ENDOMETRIOSIS BY MULTICOLOR FLUORESCENCE IN-SITU HYBRIDIZATION (FISH)

Endometriosis affects 10-15% of women of reproductive age and is a com mon cause of infertility and pelvic pain. Although endometriosis is ch aracterized by abnormal growth or turn-over of cells, the genetic chan ges involved remain unclear. We employed a multi-color fluorescence in situ hybridization (FISH) strategy to determine the incidence of soma tic chromosomal numeric alterations in severe/late stage endometriosis . Using alpha-satellite sequence-specific DNA probes for chromosomes 7 , 8, 11, 12, 16, 17, and 18, simultaneous two- and three-color FISH we re performed to evaluate the frequency of monosomic, disomic, and tris omic cells in normal control and endometriotic tissue specimens. In on e of four endometriosis samples studied, a significantly higher freque ncy of monosomy for chromosome 17 (14.8%, chi(4)(2) = 53.3, P < 0.0001 ) and 16 (8.8%, chi(4)(2) = 11.4, P < 0.05) was observed. An increased numb,er of cells with chromosome 11 trisomy (14.8%, chi(4)(2) = 96.2, P < 0.0001) were detected in a second case. In a third case, a distin ct colony of nuclei with chromosome 16 monosomy (14.1%, chi(4)(2) = 21 .39, P < 0.005) was detected. Acquired chromosome-specific aneuploidy may be involved in endometriosis, reflecting clonal expansion of chrom osomally abnormal cells. That candidate tumor suppressor genes and onc ogenes have been mapped to chromosomes 11, 16, and 17 suggests that ch romosomal loss or gain plays a role in the development and/or progress ion of endometriosis.