Prevalence of angiotensin-converting enzyme gene insertion-deletion polymorphism in patients with primary knee osteoarthritis.

OBJECTIVE Angiotensin converting enzyme (ACE) plays an important role in a number of inflammatory and immune related disorders. This study was undertaken to investigate an association between Angiotensin converting enzyme (ACE) gene insertion- deletion (I/D) polymorphism and primary knee osteoarthritis (OA) in Kuwait and to explore a correlation between clinical subgroups of OA and ACE I/D polymorphism genotypes. PATIENTS AND METHODS The prevalence of ACE gene I/D polymorphism was determined in 115 patients with primary knee OA and 111 ethnically matched healthy controls by using polymerase chain reaction (PCR) of the genomic DNA. The association of ACE gene I/D polymorphism genotypes was also studied with age of disease onset, function and radiological grading. RESULTS No significant difference was detected in the frequency of ACE gene I/D polymorphism genotypes and alleles between knee OA patients and the controls. The frequency of ACE gene polymorphism genotypes was also studied in subgroups on the basis of clinical parameters of age of onset of disease, function and radiological grading and no significant difference was detected between subgroups of OA patients and the controls. This is in sharp contrast to a previous report from Korea in which a significant association has been reported between ACE gene polymorphism and knee OA. CONCLUSION This study did not find an association between ACE gene I/D polymorphism genotypes in Kuwaiti patients with primary knee osteoarthritis and the onset or severity of the disease, which is very different from Korean knee OA patients in which an association has been reported.