Genetic analysis of the IL8 gene polymorphism (rs4073) in generalized aggressive periodontitis.
OBJECTIVE
Interleukin (IL)-8 is an important chemokine for regulation of the inflammatory response. A single nucleotide polymorphism (SNP) reference sequence (rs) 4073 in the IL8 gene has been shown to regulate IL-8 levels after stimulation with lipopolysaccharide. This study investigates the transmission pattern of the IL8 rs4073 risk allele A and its association with susceptibility to aggressive periodontitis (AgP) in families and in a case-control cohort of unrelated individuals from a Brazilian population.


METHODS
Genotyping was performed by standard polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP) in 13 nuclear families and 184 unrelated subjects. Statistical analysis was performed using the transmission disequilibrium test (TDT) for the family dataset and Chi-square test and multivariate logistic regression modelling for the case-control dataset.


RESULTS
TDT analyses did not detect evidence of over transmission of IL8 rs4073 alleles in affected and unaffected family members (allele T: 52%; allele A: 48%; p=0.2252). How expected, analyses of cases and unrelated controls showed a significant and inverse association of age with AgP; however, a lack of association between genotypes, ethnic groups and generalized AgP was observed.


CONCLUSIONS
The SNP (rs4073) was not associated with AgP in unrelated individuals and there is no evidence of over transmission of the alleles in families with AgP, from Brazilian individuals.
Department of Morphology, Division of Histology, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil. Electronic address: denise@andia.com.br.
Denise Carleto
DC
Andia
Department of Endodontics, School of Dentistry, University of Texas Health Science Center, Houston, TX, USA.
Ariadne
A
Letra
Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil.
Renato Corrêa Viana
RC
Casarin
Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil.
Marcio Zaffalon
MZ
Casati
Department of Morphology, Division of Histology, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil.
Sergio Roberto Peres
SR
Line
Department of Morphology, Division of Histology, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil.
Ana Paula
AP
de Souza
D010520:Aggressive Periodontitis / Q000235:genetics*; D000483:Alleles; D001938:Brazil; D016022:Case-Control Studies; D005260:Female; D005838:Genotype; D006801:Humans; D016209:Interleukin-8 / Q000235:genetics*; D008297:Male; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide
D016209:Interleukin-8