Genet. Sel. Evol. 35 (2003) S19-S34
DOI: 10.1051/gse:2003014

Application of disease-associated differentially expressed genes - Mining for functional candidate genes for mastitis resistance in cattle

Manfred Schwerin^a, Diana Czernek-Schäfer^a, Tom Goldammer^a, Srinivas R. Kata^b, James E. Womack^b, Ravi Pareek^c, Chandra Pareek^c, Krzysztof Walawski^c and Ronald M. Brunner<sup>a

a</sup>  Research Unit for Molecular Biology, Research Institute for the Biology of Farm Animals, Dummerstorf, Germany
^b  Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA
^c  Department of Animal Genetics, University of Warmia and Mazury, Olsztyn, Poland

(Accepted 4 February 2003)

Abstract
In this study the mRNA differential display method was applied to identify mastitis-associated expressed DNA sequences based on different expression patterns in mammary gland samples of non-infected and infected udder quarters of a cow. In total, 704 different cDNA bands were displayed in both udder samples. Five hundred-and-thirty two bands, (75.6%) were differentially displayed. Ninety prominent cDNA bands were isolated, re-amplified, cloned and sequenced resulting in 87 different sequences. Amongst the 19 expressed sequence tags showing a similarity with previously described genes, the majority of these sequences exhibited homology to protein kinase encoding genes (26.3%), to genes involved in the regulation of gene expression (26.3%), to growth and differentiation factor encoding genes (21.0%) and to immune response or inflammation marker encoding genes (21.0%). These sequences were shown to have mastitis-associated expression in the udder samples of animals with and without clinical mastitis by quantitative RT-PCR. They were mapped physically using a bovine-hamster somatic cell hybrid panel and a 5000 rad bovine whole genome radiation hybrid panel. According to their localization in QTL regions based on an established integrated marker/gene-map and their disease-associated expression, four genes (AHCY, PRKDC, HNRPU, OSTF1) were suggested as potentially involved in mastitis defense.

Key words: mastitis / expressed sequence tag / gene expression / cattle / RH mapping

Correspondence and reprints: Manfred Schwerin
    e-mail: schwerin@fbn-dummerstorf.de

© INRA, EDP Sciences 2003