Polymorphisms in exons 6 and 7 of the ABO locus and their association with venous thrombosis in young Brazilian patients.
The A1 and B alleles of the ABO blood system have been associated with high levels of both factor VIII and von Willebrand factor and with a predisposition to venous thromboembolism (VTE). In this study, genotypes of the ABO system were determined by PCR-restriction fragment length polymorphism for 148 young VTE Brazilian patients and 233 unrelated control individuals. The blood group O was more frequent among the controls [odds ratio (OR), 0.21; 95% confidence interval (CI), 0.13-0.34; P = 0.000) and groups A and B (OR, 2.24; 95%, CI, 1.46-3.42; P = 0.000 and OR, 2.52; 95% CI, 1.42-4.48; P = 0.002, respectively) among patients. The patients' group was under Hardy-Weinberg equilibrium, whereas the control group was not (P < 0.0051), suggesting that natural selection might be acting in favor of carriers of the O blood group. When the allelic frequencies were compared through multivariate logistic regression analysis for adjustments of covariates, the alleles A1 (OR, 1.69; 95% CI, 1.17-2.45; P = 0.006), A2 (OR, 2.19; 95% CI, 1.24-3.87; P = 0.010), and B (OR, 2.65; 95% CI, 1.64-4.26; P = 0.000) were independently associated with VTE and may represent important risk factors to the development of VTE among young Brazilian patients. Thus, the inclusion of ABO blood group determination may be helpful to discriminate individuals with high risk for VTE allowing target intervention as well as to manage VTE in young patients.
Faculty of Pharmacy, Federal University of Minas Gerais, Av. António Carlos 6627, Belo Horizonte, Minas Gerais, Brazil.
Sabrina G
SG
Paiva
Adriano P
AP
Sabino
Maria G
MG
Carvalho
Daniel D
DD
Ribeiro
Karina B
KB
Gomes
Mariana S
MS
Santos
Marina S
MS
Oliveira
Geralda G
GG
Lages
Luci M S
LM
Dusse
Ana Paula
AP
Fernandes
D000017:ABO Blood-Group System / Q000235:genetics*; D000328:Adult; D000483:Alleles; D001938:Brazil; D005091:Exons; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012150:Polymorphism, Restriction Fragment Length; D040641:Quantitative Trait Loci / Q000235:genetics*; D012307:Risk Factors; D054556:Venous Thromboembolism / Q000235:genetics; D020246:Venous Thrombosis / Q000235:genetics*
D000017:ABO Blood-Group System