GENÉTICA DA PERIODONTITE AGRESSIVA EM BRASILEIRO: RESULTADOS PRELIMINARES EM FAMÍLIAS DE ASCENDÊNCIA AFRICANA Genetics of Aggressive Periodontitis in Brazilians: Preliminary Data in African-Brazilian Families

Genetic studies on aggressive periodontitis in Brazilians are still scarce. In this study, the segregation pattern of aggressive periodontitis was evaluated in five African-Brazilian families. In addition, preliminary molecular studies were accomplished. The results suggest that the mode of inheritance of aggressive periodontitis in these families is autossomal dominant with very high or complete penetrance. Three SNPs were found in the chromosome one with identical heterozygote genotype detected in four individuals assessed, who were different from the reference genotype (the probability of that occurring by chance in three no related people: p < 0,000005). These three SNPs are localized in the 1q32.2-32.3 interval where the presence of 17 different protein codifying genes can be observed. One of the genes, TRAF5, belongs to the family of tumoral necrosis factor receptors and is involved in the inflammatory process. The results of this preliminary study suggest that, under the hypothesis of a principle gene model for aggressive periodontitis, TRAF5 is a potential gene candidate for aggressive periodontitis in African-Brazilians. UNITERMS: aggressive periodontitis, genetic polymorphism, mode of inheritance, genotyping. revsetembro1a.pmd 19/3/2008, 13:08 39 R. Periodontia 17(3):35-40 4 0 REFERENCIAS BIBLIOGRAFICAS 1Benjamin SD, Baer PN. Familial patterns of advanced alveolar bone loss in adolescence (periodontosis). Periodontics 1967;5:82-88. 2Boughman JA, Beaty TH, Yang P, Goodman SB, Wooten RK, Susuki JB. Problems of genetic model testing in early onset periodontitis. J Periodontol 1988; 59:332-37. 3Butler JH. A familial pattern of juvenile periodontitis (periodontosis). J Periodontol 1969; 40:115-118. 4Diehl SR, Wang YF, Brooks CN. Linkage disequilibrium of interleukin1 genetic polymorphisms with early-onset periodontitis. J Periodontol 1999;70: 418-30. 5Endo M, Tai H, Tabeta K. Analysis of single nucleotide polymorphisms in the 5’-flanking region of tumor necrosis factor-alpha gene in japanese patients with early-onset periodontitis. J Periodontol 2001; 72:1554-59. 6Gonzales JR, Michel J, Diete A. Analysis of genetic polymorphisms at the interleukin-10 loci in aggressive and chronic periodontitis. J Clin Periodontol 2002; 29:816-22. 7Gonzales JR, Kobayashi T, Michel J. Interleukin-4 gene polymorphisms in japanese and caucasian patients with aggressive periodontitis. J Clin Periodontol 2004;31:384-89. 8Gravallese EM, Golson DL, Goldring SR, Auron PE. The role of TNFreceptor family members and other TRAF-dependent receptors in bone resorption. Arth Res 2001;3:6-12. 9Herr A, Grutzmann R, Matthaei A, Artelt J, Schrock E, Rump A, Pilarsky C. High-resolution analysis of chromossomal imbalances using the Affymetrix 10K genotyping chip. Genom 2005;85(3):392-400. 10Hodge PJ, Michalowicz BS. Genetic predisposition to periodontitis in children and young adults. Periodontol 200