title: Tumor necrosis factor haplotype diversity in Mestizo and native populations of Mexico.
abstract: The so-called tumor necrosis factor (TNF) block includes the TNFA, lymphotoxin alpha and beta (LTA and LTB) genes with single-nucleotide polymorphisms (SNP) and microsatellites with an allele frequency that exhibits interpopulation variability. To date, no reports have included both SNPs and microsatellites at the TNF block to study Mestizo or Amerindian populations from Mexico. In this study, samples of five Mexican Mestizo populations (Durango, Guadalajara, Monterrey, Puebla, and Tierra Blanca) and four native-Mexican populations (North Lacandonians, South Lacandonians, Tepehuanos, and Yaquis) were genotyped for two SNPs (LTA+252A>G and TNFA-308G>A) and four microsatellites (TNFa, d, e, and f), to analyze the genetic substructure of the Mexican population. Allele and haplotype frequencies, linkage disequilibrium (LD), and interpopulation genetic relationships were calculated. There was significant LD along almost all of the TNF block but the lowest D' values were observed for the TNFf-TNFd pair. Mestizos showed higher allele and haplotype diversity than did natives. The genetic differentiation level was reduced among Mestizos; however, a slightly, but significant genetic substructure was observed between northern and southern Mexican Mestizos. Among the Amerindian populations, the genetic differentiation level was significantly elevated, particularly in both North and South Lacandonians. Furthermore, among Southern Lacandonians, inhabitants of Lacanja town were the most differentiated from all the Mexicans analyzed. The data presented here will serve as a reference for further population and epidemiological studies including these TNF polymorphisms in the Mexican population.
authors: Molecular Medicine Division, Centro de Investigación Biomédica de Occidente (CIBO), Instituto Mexicano del Seguro Social (IMSS), Guadalajara, Mexico; Doctorate Program in Human Genetics, Universidad de Guadalajara, Guadalajara, Mexico.
authors: X H
authors: XH
authors: Castro-Martínez
authors: C
authors: C
authors: Leal-Cortés
authors: S E
authors: SE
authors: Flores-Martínez
authors: A G
authors: AG
authors: García-Zapién
authors: J
authors: J
authors: Sánchez-Corona
authors: E
authors: E
authors: Portilla-de Buen
authors: I
authors: I
authors: Gómez-Espinel
authors: I
authors: I
authors: Zamora-Ginez
authors: R
authors: R
authors: Pérez-Fuentes
authors: S
authors: S
authors: Islas-Andrade
authors: C
authors: C
authors: Revilla-Monsalve
authors: F
authors: F
authors: Guerrero-Romero
authors: M
authors: M
authors: Rodríguez-Morán
authors: F
authors: F
authors: Mendoza-Carrera
mesh_terms: D005260:Female; D006239:Haplotypes; D006801:Humans; D007198:Indians, North American / Q000235:genetics*; D015810:Linkage Disequilibrium; D008297:Male; D008800:Mexico; D018895:Microsatellite Repeats; D020641:Polymorphism, Single Nucleotide; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D014409:Tumor Necrosis Factor-alpha
keywords: LTA+252A>G; Mexican Mestizo; Mexican native; TNF microsatellite; TNF-308G>A; genetic diversity