FOXO3a gene polymorphism and bronchial asthma in Egyptian children

Document Type : Original Article

Authors

1 Department of Pediatrics, Faculty of Medicine, Cairo University, Cairo, Egypt.

2 Department of Clinical Pathology, Faculty of Medicine, Cairo University, Cairo, Egypt.

Abstract

Background: FOXO3a proteins play multiple crucial roles in immune
response. FOXO3 inhibits T cell proliferation, induces T cell apoptosis via
upregulation of proapoptotic proteins and it suppresses T cell activation
preventing autoimmunity. The role of FOXO3a gene in the pathogenesis of
bronchial asthma has been studied in few ethnic groups and revealed its
implication in asthma pathogenesis. Objectives: The aim of the current study is
to detect the association between single nucleotide polymorphism of the
FOXO3a gene (rs13217795) and bronchial asthma, atopy and asthma severity
in Egyptian children. Methods: The current cross-sectional case-control study
was performed on 75 asthmatic children aged 2 to 12 years following up in the
pulmonology outpatient clinic in Children's hospital, Cairo University and 75
age and sex matched healthy controls. Candidates were subjected to clinical
evaluation in addition to genotyping for the FOXO3a gene polymorphism using
PCR-RFLP technique. Results: The highest frequency was for the heterozygous
type CT in both cases and controls groups. The genotype frequencies of mutant
type TT for cases and controls were 12 % and 16% respectively, and the T allele
frequencies were 37.2% in cases and 46.7% in the control group while CC
genotype was present in 37.3% of asthmatic patients and 22.6% in the controls
and the C allele was detected in 62.8% and 53.3% for cases and controls
respectively. No statistically significant differences were observed between
asthmatic patients and controls regarding the different genotypes of the
FOXO3a gene polymorphism (p=0.161). No significant association was
detected between the different genotypes of the FOXO3a gene polymorphism
and the atopic status (p=0.536) or the different grades of asthma severity (p=
0.545). Conclusions: The study of FOXO3a gene polymorphism (rs13217795)
in asthmatic Egyptian children revealed low frequency of the mutant TT
genotype among cases and controls. In the current study, FOXO3a
polymorphism has no role in the pathogenesis of asthma or atopy. Moreover, it
has no relation to degree of disease severity.

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