A functional interleukin‐1β gene polymorphism is associated with chronic periodontitis in a sample of Brazilian individuals

Abstract

The chronic periodontitis group displayed a higher percentage of the T allele (28%) when compared to the aggressive periodontitis group (10.7%, chi(2)=5.24, p=0.02, OR=0.31, CI=0.11--0.88) and to control group (8.7%, chi(2)=7.11, p=0.007, OR=0.24, CI=0.08--0.73). Our data suggested that the polymorphism in the locus +3954 of IL1 B gene could be a risk factor for chronic periodontitis in a sample of Brazilian individuals.

An Interleukin-1β (IL-1β) Single-Nucleotide Polymorphism at Position 3954 and Red Complex Periodontopathogens Independently and Additively Modulate the Levels of IL-1β in Diseased Periodontal Tissues

“…Regarding ethnic status, Caucasians were prevalent compared with Afro-Americans/mulatto individuals; however, no further analysis was performed based on such classification in view of the high genetic miscegenation of the Brazilian population (40). The frequencies of IL-1␤(3954) genotypes and alleles were found to be similar in the CP and C groups (Table 3) and were also found to be similar to those reported for the Brazilian population in previous studies (4,34,56).…”

“…While some studies associated the IL-1␤(3954) T allele with an increased risk for severe periodontitis development, others did not confirm such an association (12,17,27,34,48), and the relevance of IL-1␤(3954) to the periodontitis outcome is still controversial (17,48). Genetic studies in multifactorial complex trait diseases such as periodontitis are indeed complex, and the observance (or not) of covariates (such as smoking and specific bacteria) involved in periodontal-disease pathogenesis and the criteria to select diseased and C groups may hinder their interpretation (17,48).…”

“…DNA was extracted from epithelial buccal cells with a sequential phenol-chloroform solution and precipitated with a salt/ ethanol solution (46). For genotyping IL-1␤(3954) SNP, DNA fragments were amplified by the use of primer pairs 5Ј-CTCAGGTGTCCTCGAAGAAATCA AA-3Ј and 5Ј-GCTTTTTTGCTGTGAGTCCCG-3Ј (194 bp), as previously described (34). A 15-l aliquot of the PCR product was subjected to restriction fragment length polymorphism (RFLP) with 3 U of TacI (Promega) at 65°C overnight, and the products were resolved and separated on a 2% agarose gel stained with SYBRsafe (Invitrogen Life Technologies, Carlsbad, CA) in order to yield C (85 ϩ 97 ϩ 12 bp) and T (182 ϩ 12 bp) alleles, allowing, therefore, the determination of the CC, CT, and TT genotypes.…”

Polimorfismo de citoquinas relacionadas ao processo inflamatório periodontal

“…Assim, o polimorfismo gênico tem sido considerado como instrumento importante para identificar indivíduos susceptí-veis a doenças com patogênese inflamatória (DUFF, 1998;SOGA et al, 2003). O risco genético para o desenvolvimento da periodontite vem sendo estudado em populações distintas, uma vez que forte relação com os grupos étni-cos e raciais pode ser traçada com o polimorfismo das citoquinas estudadas (PAPAPANOU et al, 2001;MOREIRA et al, 2005). Além disso, a possibilidade de associação do fator de risco genético com outros fatores de risco, como fumo e diabetes mellitus, é levantada por alguns trabalhos (PARKHILL et al, 2000;GUZMAN et al, 2003;MEISEL et al, 2003).…”

“…No entanto, trabalhos subseqüentes podem não observar tal relação e ainda envolvem, em suas pesquisas, outras citoquinas também presentes no processo inflamatório (YAMAZAKI et al, 2001;ANUSAKSATHIEN et al, 2003;MOREIRA et al, 2005;TREVILATTO et al, 2003;GONZALES et al, 2004;FOLWACZNY et al, 2005b).…”