title: Impact of population admixture on the distribution of immune response co-stimulatory genes polymorphisms in a Brazilian population.
abstract: Co-stimulatory molecules are essential in the orchestration of immune response and polymorphisms in their genes are associated with various diseases. However, in the case of variable allele frequencies among continental populations, this variation can lead to biases in genetic studies conducted in admixed populations such as those from Brazil. The aim of this study was to evaluate the influence of genomic ancestry on distributions of co-stimulatory genes polymorphisms in an admixed Brazilian population. A total of 273 individuals from the north of Brazil participated in this study. Nine single nucleotide polymorphisms in 7 genes (CD28, CTLA4, ICOS, CD86, CD40, CD40L and BLYS) were determined by polymerase chain reaction-restriction fragment length polymorphism. We also investigated 48 insertion/deletion ancestry markers to characterize individual African, European and Amerindian ancestry proportions in the samples. The analysis showed that the main contribution was European (43.9%) but also a significant contribution of African (31.6%) and Amerindian (24.5%) ancestry. ICOS, CD40L and CD86 polymorphisms were associated with genomic ancestry. However there were no significant differences in the proportions of ancestry for the other SNPs and haplotypes studied. Our findings reinforce the need to apply AIMs in genetic association studies involving these polymorphisms in the Brazilian population.
authors.affiliation: Universidade Estadual Paulista, Instituto de Biociências, Letras e Ciências Exatas, São José do Rio Preto, Brazil; Faculdade de Medicina de São José do Rio Preto, Centro de Investigação de Microrganismos, São José do Rio Preto, Brazil. Electronic address: gcapatti@hotmail.com.
authors.forename: Gustavo Capatti
authors.initials: GC
authors.lastname: Cassiano
authors.affiliation: Universidade Federal do Pará, Instituto de Ciências Biológicas, Belém, Brazil.
authors.forename: Eduardo José Melo
authors.initials: EJ
authors.lastname: Santos
authors.affiliation: Universidade Federal do Pará, Instituto de Ciências Biológicas, Belém, Brazil.
authors.forename: Maria Helena Thomaz
authors.initials: MH
authors.lastname: Maia
authors.affiliation: Faculdade de Medicina de São José do Rio Preto, Centro de Investigação de Microrganismos, São José do Rio Preto, Brazil.
authors.forename: Adriana da Cruz
authors.initials: Ada C
authors.lastname: Furini
authors.affiliation: Universidade Federal do Sergipe, Departamento de Biologia, Aracaju, Brazil.
authors.forename: Luciane Moreno
authors.initials: LM
authors.lastname: Storti-Melo
authors.affiliation: Faculdade de Medicina de São José do Rio Preto, Centro de Investigação de Microrganismos, São José do Rio Preto, Brazil.
authors.forename: Franciele Maira Batista
authors.initials: FM
authors.lastname: Tomaz
authors.affiliation: Faculdade de Medicina de São José do Rio Preto, Centro de Investigação de Microrganismos, São José do Rio Preto, Brazil.
authors.forename: Pamella Cristina Alves
authors.initials: PC
authors.lastname: Trindade
authors.affiliation: Universidade Estadual Paulista, Instituto de Biociências, Letras e Ciências Exatas, São José do Rio Preto, Brazil; Faculdade de Medicina de São José do Rio Preto, Centro de Investigação de Microrganismos, São José do Rio Preto, Brazil.
authors.forename: Marcela Petrolini
authors.initials: MP
authors.lastname: Capobianco
authors.affiliation: Universidade Federal do Pará, Laboratório de Genética Humana e Médica, Belém, Brazil.
authors.forename: Marcos Antônio Trindade
authors.initials: MA
authors.lastname: Amador
authors.affiliation: Laboratório de Pesquisas Básicas em Malária, Instituto Evandro Chagas, Secretaria de Vigilância em Saúde, Ananindeua, Brazil.
authors.forename: Giselle Maria Rachid
authors.initials: GM
authors.lastname: Viana
authors.affiliation: Laboratório de Pesquisas Básicas em Malária, Instituto Evandro Chagas, Secretaria de Vigilância em Saúde, Ananindeua, Brazil.
authors.forename: Marinete Marins
authors.initials: MM
authors.lastname: Póvoa
authors.affiliation: Universidade Federal do Pará, Laboratório de Genética Humana e Médica, Belém, Brazil.
authors.forename: Sidney Emanuel Batista
authors.initials: SE
authors.lastname: Santos
authors.affiliation: Universidade Estadual Paulista, Instituto de Biociências, Letras e Ciências Exatas, São José do Rio Preto, Brazil; Laboratório de Pesquisas Básicas em Malária, Instituto Evandro Chagas, Secretaria de Vigilância em Saúde, Ananindeua, Brazil.
authors.forename: Ricardo Luiz Dantas
authors.initials: RL
authors.lastname: Machado
mesh_terms: D000483:Alleles; D001938:Brazil; D002874:Chromosome Mapping; D061025:Costimulatory and Inhibitory T-Cell Receptors / Q000235:genetics*; D005006:Ethnicity / Q000235:genetics; D019143:Evolution, Molecular; D005260:Female; D005787:Gene Frequency; D005828:Genetics, Population; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D054643:INDEL Mutation; D007109:Immunity / Q000235:genetics*; D015810:Linkage Disequilibrium; D008297:Male; D020641:Polymorphism, Single Nucleotide
chemical_list: D061025:Costimulatory and Inhibitory T-Cell Receptors
keywords: Admixture population; Ancestry markers; Immunogenetics