A critical analysis of disease-associated DNA polymorphisms in the genes of cattle, goat, sheep, and pig

Abstract

Genetic variations through their effects on gene expression and protein function underlie disease susceptibility in farm animal species. The variations are in the form of single nucleotide polymorphisms, deletions/insertions of nucleotides or whole genes, gene or whole chromosomal rearrangements, gene duplications, and copy number polymorphisms or variants. They exert varying degrees of effects on gene action, such as substitution of an amino acid for another, shift in reading frame and premature termination of translation, and complete deletion of entire exon(s) or gene(s) in diseased individuals. These factors influence gene function by affecting mRNA splicing pattern or by altering/eliminating protein function. Elucidating the genetic bases of diseases under the control of many genes is very challenging, and it is compounded by several factors, including host × pathogen × environment interactions. In this review, the genetic variations that underlie several diseases of livestock (under monogenic and polygenic control) are analyzed. Also, factors hampering research efforts toward identification of genetic influences on animal disease identification and control are highlighted. A better understanding of the factors analyzed could be better harnessed to effectively identify and control, genetically, livestock diseases. Finally, genetic control of animal diseases can reduce the costs associated with diseases, improve animal welfare, and provide healthy animal products to consumers, and should be given more attention.

Single nucleotide polymorphisms in immunity-related genes and their association with mastitis in Chilean dairy cattle

“…Several genome-scan studies have identified quantitative trait loci and several molecular markers, such as single nucleotide polymorphisms (SNPs), that are related to mastitis, suggesting that resistance to the condition has a significant genetic component despite its low heritability (Klungland et al, 2001;Heringstad et al, 2003;Holmberg and Andersson-Eklund, 2004;Khatkar et al, 2004;Ogorevc et al, 2009). Indeed, some studies have demonstrated variations or polymorphisms in genes related to immune response that could be associated with mastitis resistance (Detilleux, 2002;Ibeagha-Awemu et al, 2008).…”

Marcadores moleculares asociados al veteado de la carne en bovinos Criollos uruguayos

“…También subrayan la importancia de estudios poblacionales previos a la implementación de selección asistida por marcadores. Estos estudios, junto con el análisis de la validez de los marcadores en los distintos sistemas de producción, son fundamentales para determinar el alcance y eficacia de posibles planes de mejora genética que utilicen marcadores moleculares (Ibeagha-Awemu et al, 2008;Neuner et al, 2009). El análisis fenotípico y de otros marcadores relacionados con la calidad de la carne en estas poblaciones permitirá evaluar el potencial productivo del bovino Criollo Uruguayo y sus cruzas, en el marco de la caracterización y conservación de los recursos genéticos animales mundiales.…”

The Application of Genomic Technologies to Investigate the Inheritance of Economically Important Traits in Goats

“…Unfortunately, causal mutations have been identified only for a few Mendelian genetic disorders (Table 3, [117][118][119][120][121]). …”