Objective: To test the association of K469E, the common intercellular adhesion molecule-1 (ICAM-1) polymorphism with chronic obstructive pulmonary disease (COPD) and expression of ICAM-1 in Han people of Central and South Region in China.
Methods: A case-control study was done on 91 patients with COPD and 80 matched controls of Han people from central and south region in China, mainly from Hunan Province. Genomic DNA was extracted from white blood cells. ICAM-1 sequences were amplified by PCRand analyzed by agarose gel electrophoresis. Genotypes were defined by base sequencing. In addition, soluable intercellular adhesion molecule-1 (sICAM-1) serum levels were measured in 86 people picked out randomly from the COPD group and the control group.
Results: There was no difference in the frequency of the genotype and allele between the COPD group and the controls, but compared with those who were not very severe, the frequency of KE/ EE genotypes and E allele in COPD patients at very severe stage was significantly higher (10/16 vs 26/75, 12/30 vs 20/150, P<0.05). The level of sICAM-1 increased in the COPD patients, with negative correlation to forced expiratory volume in one second for the percentage of predicted value (FEV1%). But in both COPD patients and controls, the level of sICAM-1 did not differ significantly in different genotypes(P>0.05).
Conclusion: K469E polymorphism of ICAM-1 may not affect the susceptibility of COPD and the expression of ICAM-1 in Han people from central and south of China in this study, but carriers of E allele are at high risk of developing severe stage of COPD.