Polymorphisms of the cytokine genes TGFB1 and IL10 in a mixed-race population with Crohn's disease.
BACKGROUND
Most Crohn's disease (CD) genes discovered in recent years are associated with biological systems critical to the development of this disease. TGFB1 and IL10 are cytokines with important roles in CD. The aim of this study was to evaluate the association between CD, its clinical features and TGFB1 and IL10 gene polymorphisms.


METHODS
This case-control study enrolled 91 patients and 91 controls from the state of Bahia, Brazil. Five single nucleotide polymorphisms (SNPs) were studied in the TGFB1 gene (codon 10 T > C--rs1800470; codon 25 G > C--rs1800471) and IL10 gene (-1082 A > G--rs1800896; -819 T > C--rs1800871; -592 A > C--rs1800872). An analysis of the genetic polymorphisms was performed using a commercial kit. A comparison of allele frequencies and genotypes was estimated by calculating the odds ratio (OR) with a confidence interval adjusted via the Bonferroni test for a local alpha of 1%. A stratified analysis was applied for gender, race and smoking history. Patients with CD were characterized according to the Montreal classification.


RESULTS
The C allele and CC genotype of the TGFB1 gene rs1800470 were both significantly associated with CD. The stratified analysis showed no confounding factors for the co-variables of gender, race and smoking history. The IL10 gene rs1800896 G allele was significantly associated with age at diagnosis of CD, while the T allele of the IL10 gene rs1800871 was significantly associated with perianal disease. The SNPs rs1800871 and rs1800872 were in 100% linkage disequilibrium.


CONCLUSIONS
TGFB1 gene polymorphisms may be associated with susceptibility to the development of CD, and IL10 gene polymorphisms appear to influence the CD phenotype in this admixed population.
Federal University of Bahia, Salvador, Brazil. neoalmeida@yahoo.com.br.
Neogelia Pereira
NP
Almeida
Genoile Oliveira
GO
Santana
Tamara Celi
TC
Almeida
Maria Teresita
MT
Bendicho
Denise Carneiro
DC
Lemaire
Mauricio
M
Cardeal
André Castro
AC
Lyra
D000293:Adolescent; D000328:Adult; D000368:Aged; D001938:Brazil; D016022:Case-Control Studies; D003424:Crohn Disease / Q000235:genetics*; D003710:Demography; D005006:Ethnicity / Q000235:genetics*; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D044469:Racial Groups / Q000235:genetics*; D053773:Transforming Growth Factor beta1 / Q000235:genetics*; D055815:Young Adult
C508609:IL10 protein, human; C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1; D016753:Interleukin-10