Genetic diversity of a brazilian Creole cattle based on fourteen microsatellite loci

El bovino Criollo Brasileño fue introducido en América durante la colonización en el siglo XVI. A lo largo de cuatro siglos, estos animales se vienen desarrollando por selección natural, demostrando alta adaptación a las condiciones ambientales. Hoy se encuentra en riesgo de extinción, ya que su población no pasa de 500 animales. El presente trabajo evaluó la diversidad genética de catorce loci de microsatélites (TGLA227, ETH225, UW53, MM12, URB002, BM1824, RM088, BM1074, BM6315, ILSTS002, IDVGA51, BM1500, BMS3004, BMS3013) en una muestra de 73 animales, comparándola con otras poblaciones bovinas. En la comparación con otras dos razas Brasileñas, el ganado Criollo presentó 23 alelos exclusivos. La comparación de esos datos con algunas razas españolas y portuguesas que podrían haber originado al Criollo Brasileño sería de gran interés para confirmar la ocurrencia o no de estos alelos exclusivos en la población del Criollo brasileño

Polimorfismos de los codones 136 y 171 del gen prp en una majada de ovino criollo del uruguay

Scrapie is a transmissible neurodegenerative disorder of sheeps and goats. It is characterized by the deposition in the central nervous system of an abnormal isoform of a normal cellular protein (PrP c ), coded by the PrP gene. Mutations at 136, 154 and 171 codons of exon 2, are described. Combinations of these codons show different levels of association with the susceptibility to this disease; from highly resistants (ARR/ARR) to highly susceptibles (VRQ/VRQ). Codons 171 and 136 are the main determinant of scrapie susceptibility while codon 154 plays a minor role. In the present communication, a sample of Uruguayan Creole sheeps (N=28) was analysed for 136 and 171 codons. Samples of genomic DNA were processed by PCR-RFLP. The results were obtained by electrophoresis in polyacrylamide gel (10.5%) stained with AgNO 3 . Genotypic frequen- cies for the 136 and 171 codons were analysed. The results revealed 5 different genotypes. The most frequent genotypes were those associated with more susceptibility to the disease: VQ/AQ= 0.39 y AQ/AQ= 0.29. The analysis of genetic risk revealed a 72% of highly susceptible individuals, in case of proper environmental conditions.El scrapie es una enfermedad neuro- degenerativa transmisible de ovinos y caprinos. Se caracteriza por la acumulación en el sistema nervioso central de una isoforma anómala de una proteína celular normal (PrP c ) codificada por el gen PrP. En el exón 2 del gen se han identificado mutaciones en los codones 136, 154 y 171. La combinación de estos codones muestran diferen- tes niveles de asociación con la susceptibilidad a la enfermedad, desde muy resistentes (ARR/ ARR) a muy susceptibles (VRQ/VRQ). Los codones 171 y 136 son los mayores determinantes de la susceptibilidad al scrapie, mientras que el codón 154 juega un rol menor. En el presente trabajo se estudió una muestra de ovinos Criollos Uruguayos (N=28) para los codones 136 y 171. Las muestras de ADN genómico se procesaron por PCR-RFLP. Los resultados se obtuvieron por electroforesis en geles de poliacrilamida (10,5%) teñidos con AgNO 3 . Se analizaron las frecuencias genotípicas para los codones 136 y 171. Cinco genotipos diferentes fueron obtenidos, encontrándose en mayor frecuencia los genotipos de alta suscepti- bilidad: VQ/AQ= 0,39 y AQ/AQ= 0,29. El análisis de riesgo genético de esta majada según los genotipos obtenidos, reveló un 72% de animales muy sus- ceptibles a la enfermedad en caso de manifestar- se las condiciones ambientales propicias

Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil: Do the patterns of variation coincide?

A total of 2,708 individuals from the European-derived population of Rio Grande do Sul, divided into seven mesoregions, and of 226 individuals of similar origin from Santa Catarina were studied. Seventeen protein genetic systems, as well as grandparents' nationalities, individuals' surnames, and interethnic admixture were investigated. The alleles which presented the highest and lowest differences were GLO1*2 (16%) and PGD*A (2%), respectively, but in general no significant genetic differences were found among mesoregions. The values observed were generally those expected for individuals of European descent, with the largest difference being a lower prevalence (34-39%) of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. The Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Sul was estimated to be as high as 11%. Based on the four data sets, the most general finding was a tendency for a northeast-southwest separation of the populations studied. Seven significant phenotype associations between systems were observed at the 5% level (three at the 0.1% level). Of the latter, the two most interesting (since they were also observed in other studies) were MNSs/Duffy and Rh/ACP

Genetics, surnames, grandparents' nationalities, and ethnic admixture in Southern Brazil: Do the patterns of variation coincide?

A total of 2,708 individuals from the European-derived population of Rio Grande do Sul, divided into seven mesoregions, and of 226 individuals of similar origin from Santa Catarina were studied. Seventeen protein genetic systems, as well as grandparents' nationalities, individuals' surnames, and interethnic admixture were investigated. The alleles which presented the highest and lowest differences were GLO1*2 (16%) and PGD*A (2%), respectively, but in general no significant genetic differences were found among mesoregions. The values observed were generally those expected for individuals of European descent, with the largest difference being a lower prevalence (34-39%) of P*1. Significant heterogeneity among mesoregions was observed for the other variables considered, and was consistent with historical records. The Amerindian contribution to the gene pool of European-derived subjects in Rio Grande do Sul was estimated to be as high as 11%. Based on the four data sets, the most general finding was a tendency for a northeast-southwest separation of the populations studied. Seven significant phenotype associations between systems were observed at the 5% level (three at the 0.1% level). Of the latter, the two most interesting (since they were also observed in other studies) were MNSs/Duffy and Rh/ACP

Reconstructing History: The Amazonian Mura Indians

We studied demographic characteristics of two Mura Indian villages. Two-hundred six inhabitants of these villages and another population were tested in relation to 30 blood and 4 saliva genetic systems. These groups exhibit high mobility and exogamy rates and high fertility but relatively low mortality and variance in number of children per woman. Hb J Oxford and albumin Maku were observed, and they show high prevalences of GPT*1 and RH*R1 but low of HP*1 compared to other South American Indians. Four electrophoretic saliva systems are reported here for the first time in a predominantly Amerindian group. The amount of polymorphism was more limited than that found in Caucasian, black, and Oriental populations. The Mura are still predominantly Indian (82%) but have African (11%) and Caucasoid (7%) admixture. Using these values, the putative ancestral Mura gene frequencies were assessed. Problems related to quantitative estimations of admixture and the factors that influence the process are discussed