title: Angiotensin-converting enzyme genotype in children and coronary events in their grandparents.
abstract: BACKGROUND
  It has been suggested that the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene is an independent risk factor for coronary artery disease. The D/D genotype, which is associated with higher levels of circulating ACE than the I/D or I/I genotype, has been found significantly more frequently in patients with myocardial infarction and also in individuals with a parental history of myocardial infarction.
  
  
  RESULTS
  We explored the distribution of the ACE genotype in 404 school children, aged 6 to 13 years, and related the distribution to the number of their grandparents who had had vascular events. We found a significant association between the number of grandparents who had had coronary events and the ACE genotype (P = .01). In children with two or more grandparents who had had coronary events, there was an excess of both D/D (odds ratio = 2.8 [95% confidence interval = 1.16-6.56]) and I/D (odds ratio = 1.4 [95% confidence interval = 0.62-3.25]) genotypes compared with I/I genotypes. In addition, there was an association between the ACE genotype and lipoprotein(a) levels in children (P = .07). Both the ACE genotype and lipoprotein(a) were found to contribute significantly (P = .0042) and independently to family history of coronary artery disease, with the ACE genotype proving to be more predictive than lipoprotein(a) levels.
  
  
  CONCLUSIONS
  We conclude that the I/D polymorphism of the ACE gene is an important independent risk factor for coronary artery disease and is more predictive that lipoprotein(a). The I/D polymorphism is not only associated with a parental history of myocardial infarction but also with coronary artery disease in second-degree relatives. A further study to explore the relation between the I/D polymorphism and circulating levels of lipoprotein(a) is indicated.
authors.affiliation: Department of Cardiovascular Medicine, University of New South Wales/Prince Henry Hospital, Sydney, Australia.
authors.forename: R F
authors.initials: RF
authors.lastname: Badenhop
authors.forename: X L
authors.initials: XL
authors.lastname: Wang
authors.forename: D E
authors.initials: DE
authors.lastname: Wilcken
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003327:Coronary Disease / Q000097:blood / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012307:Risk Factors
chemical_list: D017270:Lipoprotein(a); D007703:Peptidyl-Dipeptidase A