Issue |
Genet. Sel. Evol.
Volume 36, Number 2, March-April 2004
|
|
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Page(s) | 243 - 257 | |
DOI | https://doi.org/10.1051/gse:2003061 |
DOI: 10.1051/gse:2003061
Geographic distribution of haplotype diversity at the bovine casein locus
Oliver C. Janna, Eveline M. Ibeagha-Awemua, Ceyhan Özbeyazb, Pilar Zaragozac, John L. Williamsd, Paolo Ajmone-Marsane, Johannes A. Lenstraf, Katy Moazami-Goudarzig and Georg Erhardtaa Department for Animal Breeding and Genetics, Justus-Liebig University of Giessen, Germany
b Department of Zootechnics, Faculty of Veterinary Medicine, University of Ankara, Turkey
c Laboratorio de Genetica Bioquimica y Grupos Sanguineos, Facultad Veterinaria, Zaragoza, Spain
d Roslin Institute (Edinburgh), Midlothian, Scotland, EH25 9PS, UK
e Institute of Zootechnics, Catholic University of Sacred Heart, Piacenza, Italy
f Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
g INRA-LGBC, Domaine de Vilvert, 78352 Jouy-en-Josas, France
(Received 1 October 2002; accepted 10 September 2003)
Abstract
The genetic diversity of the casein locus in cattle was studied
on the basis of haplotype analysis. Consideration of recently described
genetic variants of the casein genes which to date have not been the subject
of diversity studies, allowed the identification of new haplotypes.
Genotyping of 30 cattle breeds from four continents revealed a
geographically associated distribution of haplotypes, mainly defined by
frequencies of alleles at CSN1S1 and CSN3. The genetic diversity within
taurine breeds in Europe was found to decrease significantly from the south to
the north and from the east to the west. Such geographic patterns of cattle genetic
variation at the casein locus may be a result of the domestication process
of modern cattle as well as geographically differentiated natural or
artificial selection. The comparison of African Bos taurus and Bos indicus
breeds allowed the identification of several Bos indicus specific haplotypes
(CSN1S1*C-CSN2*A
2-CSN3*A
I / CSN3*H
) that are not found in pure
taurine breeds. The occurrence of such haplotypes in southern European breeds also
suggests that an introgression of indicine genes into taurine breeds
could have contributed to the distribution of the genetic variation observed.
Key words: casein / haplotype / Bos taurus / Bos indicus / phylogeny
Correspondence and reprints: Georg Erhardt Georg.Erhardt@agrar.uni-giessen.de
© INRA, EDP Sciences 2004