Angiotensin-converting enzyme insertion/deletion gene polymorphism is associated with dermatomyositis

Abstract

Background and objective: The cornerstone of dermatomyositis (DM) pathogenesis involves vascular disturbance that leads to hypoxia, capillary necrosis and muscle perifascicular atrophy. Hence, the hypothesis is that the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism could be associated with susceptibility to DM. Method: A single centre, case control study that genotyped ACE gene in 88 DM and 99 healthy individuals. The ACE gene polymorphism was determined by melting curve analysis of real-time polymerase chain reaction products using SYBR Green. Results: The DM and the control subjects had a comparable mean age, gender frequency and ethnicity. The frequency of the D allele was higher in DM than in the control individuals (63.6% vs 55.6%, respectively). The DM had more ACE D/D and less ACE I/D genotype when compared to the control individuals, whereas the ACE I/I genotype distribution was similar in both case and control groups. Moreover, after sex-age-adjusted analysis, the ACE D/D genotype was strongly associated with DM disease (odds ratio (OR) 2.44, 95% confidence interval (CI): 1.17–4.37), in contrast to ACE I/D genotype (OR 0.51, 95% CI: 0.28–0.93). Conclusions: Homozygous ACE D/D was associated significantly with the DM risk. Further investigations are required to clarify and to confirm the association of these genes with DM susceptibility.