Intercellular adhesion molecule-1 (ICAM-1) gene polymorphism and endometriosis in northern Iran

Endometriosis is a chronic pleomorphic disorder with pelvic or systemic manifestations, and is characterized by the presence of endometrial glands and stroma. It is generally considered to involve genetic, environmental, immunological, angiogenic and endocrine processes. The aim of this study was to evaluate the frequency of intercellular adhesion molecule-1 (ICAM-1) polymorphism at position 241 in exon 4 of the ICAM-1 gene in patients with endometriosis and in healthy control subjects in northern Iran. A total of 84 unrelated patients and 120 consecutive unrelated healthy controls from the northern Iran were recruited for the study. ICAM-1 codon 241 polymorphism analysis was performed by two independent PCR reactions, based on the two set of oligoprimers specific for Arg (AGG) or Gly (GGG) coding sequence, respectively. Genotype distributions of ICAM-1 gene show significant difference between patients and controls. The R241 allele was detected in 23% of endometriosis patients and in 6% of controls (P = 0.001; odds ratio 4.67; 95% confidence interval 1.81-12.07). Comparing patients with different stage of endometriosis, we found a trend to higher frequency of R241 in patients with stage IV (65 vs 6%; P < 0.0001). Our results suggest that ICAM-1 polymorphism in codon 241 is associated with the development of endometriosis susceptibility in the population of northern Iran.