title: Genetic ancestry is associated with colorectal adenomas and adenocarcinomas in Latino populations.
abstract: Colorectal cancer rates in Latin American countries are less than half of those observed in the United States. Latin Americans are the resultant of generations of an admixture of Native American, European, and African individuals. The potential role of genetic admixture in colorectal carcinogenesis has not been examined. We evaluate the association of genetic ancestry with colorectal neoplasms in 190 adenocarcinomas, 113 sporadic adenomas and 243 age- and sex-matched controls enrolled in a multicentric case-control study in Colombia. Individual ancestral genetic fractions were estimated using the STRUCTURE software, based on allele frequencies and assuming three distinct population origins. We used the Illumina Cancer Panel to genotype 1,421 sparse single-nucleotide polymorphisms (SNPs), and Northern and Western European ancestry, LWJ and Han Chinese in Beijing, China populations from the HapMap project as references. A total of 678 autosomal SNPs overlapped with the HapMap data set SNPs and were used for ancestry estimations. African mean ancestry fraction was higher in adenomas (0.13, 95% confidence interval (95% CI)=0.11-0.15) and cancer cases (0.14, 95% CI=0.12-0.16) compared with controls (0.11, 95% CI=0.10-0.12). Conditional logistic regression analysis, controlling for known risk factors, showed a positive association of African ancestry per 10% increase with both colorectal adenoma (odds ratio (OR)=1.12, 95% CI=0.97-1.30) and adenocarcinoma (OR=1.19, 95% CI=1.05-1.35). In conclusion, increased African ancestry (or variants linked to it) contributes to the increased susceptibility of colorectal cancer in admixed Latin American population.
authors: 1] Grupo de Investigacion Epidemiologica, Instituto Nacional de Cancerologia de Colombia, Bogota, Colombia [2] The Roslin Institute, The University of Edinburgh, Edinburgh, UK.
authors: Gustavo
authors: G
authors: Hernandez-Suarez
authors: 1] Grupo de Investigacion Epidemiologica, Instituto Nacional de Cancerologia de Colombia, Bogota, Colombia [2] Departamento de Quimica, Universidad Nacional de Colombia, Cundinamarca, Colombia.
authors: Maria Carolina
authors: MC
authors: Sanabria
authors: 1] Grupo de Investigacion Epidemiologica, Instituto Nacional de Cancerologia de Colombia, Bogota, Colombia [2] Departamento de Quimica, Universidad Nacional de Colombia, Cundinamarca, Colombia.
authors: Marta
authors: M
authors: Serrano
authors: Facultad de Medicina, Universidad Industrial de Santander, Bucaramanga, Colombia.
authors: Oscar F
authors: OF
authors: Herran
authors: Facultad de Medicina, Universidad Libre, Barranquilla, Colombia.
authors: Jesus
authors: J
authors: Perez
authors: Fundacion Oftalmologica de Santander, Bucaramanga, Colombia.
authors: Jose L
authors: JL
authors: Plata
authors: Department of Pediatrics and Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, LA, USA.
authors: Jovanny
authors: J
authors: Zabaleta
authors: 1] The Roslin Institute, The University of Edinburgh, Edinburgh, UK [2] MRC-Human Genetics Unit at the MRC IGMM, University of Edinburgh, Edinburgh, UK.
authors: Albert
authors: A
authors: Tenesa
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics*; D001741:Black or African American / Q000235:genetics; D015992:Body Mass Index; D016022:Case-Control Studies; D002681:China; D015179:Colorectal Neoplasms / Q000235:genetics*; D002149:Energy Intake; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005828:Genetics, Population; D005838:Genotype; D060005:Genotyping Techniques; D060148:HapMap Project; D006630:Hispanic or Latino / Q000235:genetics*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D044465:White People / Q000235:genetics