Gene polymorphism in transforming growth factor-beta codon 10 is associated with susceptibility to Giardiasis.
Secretory immunoglobulin A (S-IgA) antibodies have a central role in anti-Giardial defence. It has been demonstrated that transforming growth factor-beta1 (TGF-beta1) stimulates B lymphocytes to produce and secrete S-IgA. We sought to determine the association between TGF-beta1 polymorphism (T+869C) with susceptibility to Giardiasis. The TGF-beta1 genotypes and levels of salivary (S-IgA) were analysed in individuals with Giardiasis (97 symptomatic and 57 asymptomatic) and controls (n = 92). Individuals with symptomatic Giardiasis had the lowest levels of S-IgA compared to individuals in asymptomatic Giardiasis and control groups (97%, 73% and 43%, <1 g L(-1), respectively, P = 0.002). The frequency of allele C and CC genotypes of TGF-beta1 polymorphism was significantly higher among symptomatic patients than asymptomatic and control groups. Logistic regression analysis demonstrated that the individuals homozygous for allele C of TGF-beta1 had a significantly higher risk for symptomatic Giardiasis with odds ratio of 2.76 (95% CI: 3.88, 1.71, P = 0.007). Among the participants with TT genotype per cent of individuals with S-IgA level of more than 1 g L(-1) was almost twice the percentage in CC genotype individuals (14% versus 7% respectively P = 0.01). Our data suggest that CC genotype of TGF-beta1 polymorphism at codon 10 is associated with occurrence of Giardiasis.
Taherkhani
H
H
Medical Parasitology Department, Golestan University of Medical Sciences, Gorgan, Iran.
Hajilooi
M
M
Fallah
M
M
Khyabanchi
O
O
Haidari
M
M
D000483:Alleles; D003062:Codon; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005873:Giardiasis / Q000209:etiology* / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology / Q000378:metabolism; D008297:Male; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D012044:Regression Analysis; D012463:Saliva / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000235:genetics*
D003062:Codon; D007070:Immunoglobulin A; D053773:Transforming Growth Factor beta1