Gender Differences in Ancestral Contribution and Admixture in Venezuelan Populations

Abstract

The origin of the contribution of uniparental heritage were analyzed in 615 samples of individuals proceeding from 13 towns classified according to historic differences in their emergence and development as African-derived, European-derived, and admixed/urban. Mitochondrial and Y-chromosome haplogroups were identified by PCR-restriction fragment length polymorphism. The results were compared with previous estimates of admixture made with autosomal markers and with historic aspects. The results show a predominantly indigenous genetic contribution through the female, being more prevalent in urban populations; the African contribution, although dispersed, presents a larger concentration in the African-derived towns, whereas the European contribution is limited to populations with this origin, reflecting isolation and the conservation of the distribution pattern of genes of the Colonial era. With regard to admixture through males, it is almost exclusively of European origin, whereas the African contribution is basically concentrated in the African-derived towns, and the Amerindian lineages are almost nonexistent. The genome of paternal heredity, as opposed to the autosomal and the mitochondrial, shows a homogeneous pattern of admixture that is independent of the origin of the population studied, suggesting that European genes have been introduced into the Venezuelan population through male immigrations, whereas the indigenous contribution has been preserved in the Venezuelan genetic pool through the women. These results provide evidence of the heterogeneity in the genetic origin of the Venezuelan population, which should be taken into account in forensic and epidemiologic genetic studies.

Genomic biomarkers related to drug response in Venezuelan populations

“…This process began with the conquest and colonization of Venezuela and was conditioned by different historic events, generating significant genetic heterogeneity at inter-and intra-populational levels [12][13][14]. Currently, approximately 90% of the inhabitants of the country live in urban areas, which according to autosomal, Y-chromosome, and mtDNA markers reveal the predominance of the European genetic component (40-65%), followed by the Amerindian (20-35%) and, to a lesser extent, the African contribution (10-20%), with important inter-regional differences [12,14]. Moreover, indigenous people in Venezuela represent about 2.5% of the total population.…”

Polimorfismos de los genes LEP, LDLR, APOA4, sus relaciones con sobrepeso, obesidad y riesgo de enfermedades crónicas en adultos del estado Sucre, Venezuela

“…Otra investigación reportó estos hallazgos para el rs688, y encontró asociación para tres variantes más del LDLR (rs5925, rs55903358 y rs5742911) en amerindios brasileños (18). Las diferencias de los resultados de los grupos amerindios y los individuos del presente estudio, puede deberse a que los sujetos del estado Sucre provienen de una población mestiza con distintos grados de aporte europeo, amerindio y africano (29)(30)(31)(32), mientras los sujetos estudiados por Mattevi, et al (18), pertenecen a cinco poblados indígenas de Brasil con muy bajo o ningún grado de mestizaje con criollos brasileños.…”

“…Las muestras se recolectaron de personas asistentes al Hospital Universitario "Antonio Patricio de Alcalá", ciudad de Cumaná, y la Escuela de Bioanálisis de la Universidad de Oriente (UDO), núcleo Sucre. Entre los asistentes se contó con donantes voluntarios de sangre, empleados del hospital y estudiantes universitarios, entre otros, provenientes de la población general urbana de Cumaná; se trataba de individuos mestizos cuya composición genética es el resultado de una mezcla de aportes amerindios, europeos y africanos (29)(30)(31)(32). Los sujetos participantes debían cumplir con los siguientes criterios de inclusión: cuatro abuelos nacidos en el estado Sucre, no presentar relaciones de consanguinidad próxima entre sí, no padecer enfermedades agudas en el momento del estudio, ni tener trastornos de hiperglucemia (glucemia≥110 mg/dl) o diabetes.…”

rs10757278 (9p21 region) affects the risk of arterial thrombosis in male individuals from the state of anzoátegui, Venezuela

“…However, little has been studied in Latin American individuals who have high genetic and cultural variability. Genetic heterogeneity has been reported at intra and inter-regional levels in Venezuela, and also between socioeconomic status [6,7,23]. It is important to determine whether these genetic differences could be influencing the distribution of SNPs in the 9p21 region and their effect on the incidence of AT.…”

“…The Venezuelan population has shown a significant genetic heterogeneity within and between various regions of the country [5][6][7] which influences the distribution of different polymorphisms and the synergetic effect between them. For this reason, we studied the association of different SNPs in the chromosomal region 9p21, with arterial thrombotic events (AT) and present here results for three SNPs (rs2383206, rs10757274, rs10757278) in individuals with grandparents from the state of Anzoátegui, in the north-eastern portion of Venezuela.…”