Angiotensin-converting enzyme and alpha-2-macroglobulin gene polymorphisms are not associated with Alzheimer's disease in Colombian patients.

Polymorphisms in alpha-2-macroglobulin (A2M) and angiotensin-converting enzyme (ACE) genes have been considered as risk factors for Alzheimer's disease (AD) independently of the risk conferred by the apolipoprotein E sigma4 allele (APOEsigma4) in diverse populations. In the present study, we have analysed the distribution of genotypes and alleles of the insertion/deletion (I/D) polymorphisms of ACE and A2M in 83 AD patients and 69 normal controls in Colombia. Our results showed that there is no association between the I/D polymorphisms of ACE and A2M with AD (P = 0.788 and P = 0.538, respectively). Using logistic regression and multiple correlation analysis (MCA), we confirmed that the main risk factor associated and consistently grouped with AD patients in this population is APOE4, but this association was not observed with alleles and genotypes of ACE and A2M.