Objectives: To investigate if an insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene associates with HLA-DR alleles previously found to be of prognostic interest in Scandinavian sarcoidosis patients. This may contribute to characteristics associated with these HLA-DR alleles, such as a good (DR17) or poor (DR14 or 15) prognosis. DESIGN, SETTINGS AND SUBJECTS: Polymerase chain reaction (PCR) was used for analysing an I/D polymorphism in the gene coding for ACE in 138 subjects; 65 controls and 73 sarcoidosis patients, and for HLA-DR genotyping 67 patients. Serum ACE level (S-ACE) was measured in all controls and 72 patients. Sixty-one patients were classified as chronic or nonchronic after 2 years follow-up. All patients were recruited and followed at our outpatient clinic.
Results: No significant differences in ACE alleles or genotypes were seen between controls and patients or between patients positive and negative for DR17 or DR14/15. The ACE genotype did not differ between nonchronic and chronic patients. The ACE genotype tended to influence the S-ACE in patients, whilst in controls S-ACE significantly differed between the ACE genotypes.
Conclusion: This study does not support an association between ACE genotype and sarcoidosis or disease outcome. However, because significantly (P < 0.001) more DR17 positive (17 of 19) than DR14/15 positive (seven of 26) patients were classified as nonchronic, these results instead strengthen the prognostic importance of HLA-DR alleles in Scandinavian sarcoidosis patients.