ABSTRACT
La utilidad del ADN mitocondrial (ADNmt) para determinar afinidad genética entre grupos indígenas contemporáneos e inferir sobre migraciones, ha sido demostrada; pero la imposibilidad de estudiar grupos prehispánicos extintos, limita las inferencias sobre migraciones en esa época. El mestizaje en poblaciones neoamericanas ha sido caracterizado por uniones entre hombres europeos y mujeres indígenas, permitiendo detectar en la población contemporánea haplogrupos mitocondriales amerindios que informan sobre poblaciones extintas. Para conocer los linajes femeninos en el occidente de Venezuela, se estudiaron los haplogrupos del ADNmt a partir de RFLP, en una muestra de 193 individuos con antepasados procedentes del occidente de Venezuela, 81 del Estado Lara (Barquisimeto) y 112 de tres pueblos del Estado Falcón (Macu-quita=25, Macanillas=29 y Churuguara=58). Se comparó la distribución de haplogrupos entre las poblaciones y se estimó el mestizaje por línea femenina en ellas. Se comparó la distribución de cuatro haplogrupos indígenas con otras regiones de América. Se observa que en las cuatro poblaciones predominan haplogrupos amerindios, seguidos de los africanos. Al comparar la fracción indígena con el resto de América encontramos que Macanillas, Lara y Churuguara se asemejan a grupos de Amazonas y Suramérica, mientras que Macuquita a Aruba. Esto sugiere una diversidad genética importante en esa zona como probable ruta de paso hacia el sur y el Caribe; además refleja vínculos genéticos importantes entre grupos prehispánicos de Aruba y los de la Península de Paraguaná. Evidencias arqueológicas soportan estos postulados. Se recomienda aumentar la muestra y realizar análisis de secuencias para un nivel mayor de precisión.
Mitocondrial DNA (mtDNA) has been widely used to study genetic relationships between contemporary Amerindian groups and to infer ancestral migration movements; however inferences about migration routes of prehispanic extinct groups are difficult. Admixture of Neoamerican groups has been characterized by unions between European males and Amerindian females. This allows the identification in present populations of Amerindian mitocondrial haplogroups which give information on ancestral groups. In order to investigate female lineages present in western Venezuela, RFLP haplogroups from mtDNA were obtained from 193 individuals with grandparents from this region, 81 from the State of Lara (Barquisimeto) and 112 from 3 towns of the State of Falcon (Macuquita=25; Macanilla=29 and Churuguara=58). Comparison of haplogroup distributions between groups was performed, and admixture estimates based on female lineages were obtained. The distribution of four Amerindian haplogroups was compared with those of other populations from the American Continent. In our four samples Amerindian haplogroups predominate, followed by those of African origin. In the comparison of the mtDNA Amerindian fraction with other populations we find that Macanillas, Lara and Churuguara are similar to South American and Amazonian groups whilst Macuquita is similar to groups from Aruba. Our findings suggest an important genetic diversity in this region, explained by migration routes to and from the south and the Caribean. They also suggest genetic relationship between prehispanic groups from Aruba and those from the Paraguaná peninsula, which have been inferred by archeological evidences. An increase in sample size and analysis of sequences for more precision is recommended.
ABSTRACT
Se analizaron las frecuencias alélicas del locus DYS19 provenientes de 5 poblaciones rurales venezolanas deascendencia africana (Panaquire; Sotillo; Curiepe; Birongo; Ganga), y se compararon con otras 3 de ascendencia canaria (San Antonio; San Diego; Hoyo de la Cumbre) y con otras reportadas a nivel mundial, utilizando técnicas multivariantes como el Análisis de Correspondencias Binarias (ACB) y la Clasificación Automática. Se pudieron definir 4 grupos de poblaciones asociados a alelos específicos y diferentes orígenes geográficos. Todas las poblaciones venezolanas se ubicaron en el grupo europeo, lo que indica un flujo génico europeo importante por vía masculina en ellas; no obstante, el uso del ACB y la Clasificación Automática permitió diferenciar en un subgrupo a las 5 poblaciones rurales de ascendencia africana. Los resultados obtenidos reflejan la utilidad de los métodos multivariantes utilizados para maximizar el poder discriminante de loci altamente informativos como el DYS19, cuando no se dispone de recursos para estudiar varios loci simultáneamente. Además ofrecieron la posibilidad de mejorar la calidad de la información genética que se poseía sobre las poblaciones venezolanas estudiadas.
The allelic frequencies of locus DYS19 from 5 rural African-derived Venezuelan populations (Panaquire; Sotillo; Curiepe; Birongo; Ganga) were analyzed, and compared with 3 Canarian-derived Venezuelan populations (San Antonio; San Diego; Hoyo de la Cumbre) and with others reported to worldwide, using multivariate method like Correspondences Analysis and Cluster Analysis. Four population clusters were found to be associated with specific alleles and different geographic origins. All the Venezuelan populations were localized in the European cluster, which indicates the existence in them of an important European gene flow through male. Nevertheless the use of both Correspondences Analysis and Cluster Analysis simultaneously, allowed to differentiate in a sub cluster with the 5 rural African-derived Venezuelan populations. The results show the usefulness of the multivariate statistical methods to maximize the discrimination power of highly informative loci like DYS19, when resources are not available to study many loci simultaneously. Furthermore its use improved the quality of the genetic information which already existed for some of the Venezuelan populations studied.
Subject(s)
Humans , Male , Female , Hypersensitivity/classification , Hypersensitivity/diagnosis , Indigenous Peoples , Multivariate Analysis , Rural Population , Genetics , Health StatisticsABSTRACT
Four biallelic and six multiallelic Y-chromosome polymorphisms were investigated in 59 Gran Canarian, 60 North African Berber and 46 Spanish subjects. These new data were merged with equivalent literature information to obtain the parental Y-chrosomomal contribution in Gran Canarians, Colombians, and Venezuelans. The results were then compared, for Gran Canarians and Colombians, to those derived from autosomal and mtDNA. In both groups, the Spanish Y-chromosome contribution was much more marked than that estimated using mtDNA. This analysis showed a usual trend in the Spanish Colonial history, characterized by a demographic collapse of the aboriginal population, but with considerable introgression of genes through native women. In accordance to D. Ribeiro's typology for peoples subjected to Colonialism, the Y-chromosomes of these admixed populations are classified as transplanted, their mtDNA as witness, and their autosome sets as new.