Data/hora: 02/06/2024 03:40:19

Provedor de dados: 	Genetics and Molecular Biology	
País: 	Brazil	
Título: 	Linkage disequilibrium and past effective population size in native Tunisian cattle	
Autores: 	Jemaa,Slim Ben; Thamri,Nejia; Mnara,Sofiane; Rebours,Emmanuelle; Rocha,Dominique; Boussaha,Mekki.	
Data: 	2019-03-01	
Ano: 	2019	
Palavras-chave: 	Tunisian cattle; Conservation; Linkage disequilibrium; Effective population size; Single nucleotide polymorphism.	
Resumo: 	Abstract To carry out effective genome-wide association studies, information about linkage disequilibrium (LD) is essential. Here, we used medium-density SNP chips to provide estimates of LD in native Tunisian cattle. The two measures of LD that were used, mean r2 and D’, decreased from 0.26 to 0.05 and from 0.73 to 0.40, respectively, when the distance between markers increased from less than 20 Kb to 200 Kb. The decay in LD over physical distance occurred at a faster rate than that reported for European and other indigenous breeds, and reached background levels at less than 500 Kb distance. This is consistent with the absence of strong selective pressure within the Tunisian population and suggests that, in order to be effective, any potential genome-wide association mapping studies will need to use chips with higher marker density. An analysis of effective population size (Ne) based on LD data showed a decline in past Ne, with a sudden drop starting about eight generations ago. This finding, combined with the high levels of recent inbreeding revealed by runs of homozygosity (ROH) analysis, indicate that this population is endangered and may be in urgent need of a conservation plan that includes a well-designed genetic management program.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572019000100052	
Editor: 	Sociedade Brasileira de Genética	
Relação: 	10.1590/1678-4685-gmb-2017-0342	
Formato: 	text/html	
Fonte: 	Genetics and Molecular Biology  v.42 n.1 2019	
Fonte: 	info:eu-repo/semantics/openAccess