ABSTRACT
Introducción: La consanguinidad continúa siendo un fenómeno universal, hoy día los matrimonios consanguíneos y su descendencia suponen aproximadamente el 10,4 por ciento de la población mundial; sus descendientes tienen una elevada probabilidad de padecer enfermedades mendelianas recesivas, así como enfermedades complejas de naturaleza multifactorial. Objetivos: Determinar el coeficiente de endogamia de la región y las principales afectaciones encontradas en la descendencia de matrimonios consanguíneos. Métodos: Se realizó una investigación descriptiva, aplicada y retrospectiva de corte transversal sobre coeficiente de endogamia en el Consejo Popular Paso Quemado, municipio Los Palacios, Pinar del Río, en el período comprendido entre mayo 2016 y febrero 2017. Resultados: Fueron identificados 11 matrimonios consanguíneos (1,96 por ciento), mayormente en área rural y entre primos hermanos. El coeficiente de endogamia medio fue 0,00115. Después de la década del 70 no se efectuaron matrimonios consanguíneos. Afectaciones como mortalidad infantil, enfermedades monogénicas raras, malformaciones congénitas, discapacidad intelectual leve y enfermedades comunes aparecieron con mayor frecuencia en la descendencia de primos hermanos. Conclusiones: En correspondencia con la apertura de nuevas oportunidades sociales, económicas y educativas en la región la consanguinidad no constituye hoy en día un problema de salud, no obstante 52,5 por ciento de la descendencia en consanguíneos resultó afectada, mayormente por enfermedades complejas. El estudio sienta las bases para establecer una estrategia de educación y promoción de salud a nivel comunitario(AU)
Introduction: Consanguinity continues to be a universal phenomenon. Nowadays, consanguineous marriages and their descendants are estimated at 10,4 percent of the world population; their descendants have a high probability of suffering recessive Mendelian diseases, as well as complex diseases of multifactorial nature. Objectives: To determine the inbreeding coefficient of the region and the main affectations found in offspring of consanguineous marriages. Methods: A descriptive, applied and retrospective cross-sectional research on the inbreeding coefficient was conducted at Paso Quemado Popular Council, Los Palacios Municipality, Pinar del Río, from May 2016 to February 2017. Results: We identified 11 consanguineous marriages (1.96 percent), mostly in rural areas and among first cousins. The average inbreeding coefficient was 0.00115. After the 70's, there was no occurrence of consanguineous marriages. Affectations such as infant mortality, rare monogenic diseases, congenital malformations, mild intellectual disability and common diseases appeared more frequently in the offspring of first cousins. Conclusions: In correspondence with the opening of new social, economic and educational opportunities in the region, consanguinity does not constitute a health problem nowadays; however, mostly complex diseases affected 52.5 percent of offspring in consanguineous couples. The study lays the foundations to establish a health education and promotion strategy at the community level(AU)
Subject(s)
Humans , Male , Female , Consanguinity , Health Promotion , Epidemiology, Descriptive , Cross-Sectional Studies , Retrospective StudiesABSTRACT
O objetivo neste estudo foi avaliar a estrutura genética da população de bovinos da raça Girolando no Brasil. Analisou-se o arquivo de pedigree de 26.969 animais, composto de 3.031 machos e 23.938 fêmeas. O nível de conteúdo de informação do pedigree na geração atual foi 61%, mostrando ser de qualidade moderada. O coeficiente de endogamia médio e o coeficiente de relação médio da população Girolando foram 0,11 e 0,13%, respectivamente. O tamanho efetivo da população, considerando a geração completa traçada, foi 188, acima do nível crítico. Do total de 9.457 ancestrais que contribuíram para a população de referência, 457 explicaram 50% da variabilidade genética da população. O número efetivo de fundadores foi 551 e o de ancestrais 393. O intervalo médio de geração foi de 5,26 anos, sendo ligeiramente maior nas trilhas gaméticas mãe-filho e pai-filha. A partir dos coeficientes estimados, pode-se concluir que a endogamia nos rebanhos da raça Girolando foi de pequena magnitude e que as práticas de acasalamento foram adequadas durante o período avaliado. No entanto, é importante continuar com o monitoramento desses coeficientes a fim de prevenir perda de variabilidade genética.
The aim of this study was to evaluate the population structure of Girolando cattle in Brazil. The pedigree file contained 26,969 individuals, from which 3,031 were males and 23,938 were females. The average level of completeness of the pedigree in the current generation was of reasonable quality (61%). Inbreeding and average relatedness coefficients were low: 0.11 and 0.13%, respectively. Estimates of effective population size considering the full generations traced was 188, which is above the critical level range. The number of ancestors that contributed to the reference population was 9,457 animals, from which 457 explained 50% of the genetic variability of the population. The effective number of founders and the effective number of ancestors in this population were, respectively, 551 and 393. The average generation interval was 5.26 years, slightly higher in genetic pathways dam-son and sire-daughter. The inbreeding in the Girolando breed was of small magnitude, indicating that the current practices of mating were adequate during the study period. However, it is important to continue monitoring these coefficients in order to prevent loss of genetic variability.
ABSTRACT
Se realizó un estudio descriptivo, de corte trasversal en la comunidad de Guasasa del consejo popular Playa Girón, de la Ciénaga de Zapata, provincia Matanzas con el objetivo de caracterizar la consanguinidad en esta comunidad. Se determinó la frecuencia de defectos congénitos y discapacidades en la descendencia de cada tipo de matrimonio consanguíneo. Se estableció la frecuencia de los matrimonios consanguíneos en la localidad y se calculó el coeficiente de endogamia. Se identificaron 18 matrimonios consanguíneos con 66 descendientes. El retraso mental ligero estuvo presente en el 21,2 por ciento de los descendientes de los matrimonios consanguíneos, los casos se detectaron en todos los tipos de matrimonios, excepto medio primos/hermanos. El coeficiente de endogamia en la comunidad fue de 0,0033 y la frecuencia de matrimonios consanguíneos de 10,5 por ciento. Este estudio sienta las bases para establecer una estrategia de educación y promoción de salud a nivel comunitario dirigida a disminuir la frecuencia de retraso mental y otras enfermedades genéticas en la población estudiada(AU)
A descriptive, transversal cut study was carried out in the Guasasa community belonging to the Playa Girón popular council of the Ciénaga de Zapata, Matanzas province, with the goal of characterizing consanguinity in this community. The frequency of congenital defects and disabilities in the offspring of each type of consanguine marriage was determined. The frequency of consanguine marriages in the community and the endogamy coefficient were calculated. Eighteen consanguineous marriages having 66 offspring were identified. A light mental retardation was present in 21,2 percent of the offspring from these consanguineous marriages, with cases detected in all types of marriages except in the case of first cousins once removed. The endogamy coefficient in the community was 0,0033 and the frequency of consanguineous marriages turned out to be 10,5 percent. This study establishes the bases for implementing a community-level strategy for education and health promotion with the aim of decreasing mental retardation and other genetic origin diseases in the studied population(AU)
Subject(s)
Consanguinity , Intellectual Disability/genetics , Congenital Abnormalities/geneticsABSTRACT
Neste trabalho, objetivou-se comparar três estimadores do coeficiente de endogamia, F, em uma população diplóide com dois alelos, utilizando-se dados de frequências alélicas em amostras de indíviduos, com diferentes tamanhos obtidas em populações simuladas, por meio do software SAS. Foi avaliado o estimador de F, obtido pela análise de variância de frequências alélicas, o estimador considerando o método dos momentos e o estimador pelo método da máxima verossimilhança. Os resultados encontrados para a média e variância os estimadores, a partir de 1000 estimativas de F, calculadas para cada tamanho de amostra, mostraram que os três estimadores são tendenciosos. Entretanto, de maneira geral, observou-se que o estimador considerando a análise de variância foi menos tendencioso e apresentou menor variância, quando o coeficiente de endogamia da população foi alto. Para tamanho de amostra superior a 50, os três estimadores tiveram comportamento semelhante, independente da frequência alélica e da endogamia da população.
The present work evaluated the properties of three estimators of the inbreeding coefficient, F, in a diploid population with two alleles, using data of gene frequencies in individuals from random samples obtained from populations simulated through the SAS. We evaluated the estimators of F obtained by variance analysis of allelic frequencies, obtained by moment method, and estimator obtained by maximum likelihood method. The analysis of the means and variances of the estimators, obtained from 1000 estimates of F, calculated for each sample size, demonstrated that the three estimators were biased. However, it was observed that the estimator obtained from univariate analysis was less biased and presented smaller variance, when the inbreeding coefficient in the population was elevated, while for populations with low inbreeding, the variance of the estimator obtained by the multivariate analysis was smaller.