Bioscience Evidence 2024, Vol.14, No.1, 24-31 http://bioscipublisher.com/index.php/be 27 exploring and analyzing the genetic markers of cattle disease resistance, more precise and effective breeding strategies can be provided for the breeding industry. This, in turn, can enhance the disease resistance of cattle, reduce the incidence of diseases, and promote the healthy development of the livestock industry. 4 Application of GWAS in Livestock and Poultry Animals 4.1 Application of GWAS in cattle disease resistance research Cattle are among the most important livestock animals, and their disease resistance is of great significance to the breeding industry. In recent years, with the development and widespread application of GWAS technology, significant progress has been made in the study of cattle disease resistance. The application of GWAS in cattle disease resistance research mainly includes two aspects: first, discovering genetic markers related to disease resistance; second, analyzing the functional relationship between these markers and disease resistance. In cattle disease resistance research, researchers collect genotype and phenotype data from large cattle populations and use GWAS technology to analyze these data, identifying genetic markers associated with disease resistance. For example, in the study of common diseases such as mastitis, GWAS technology has been widely applied (Kurz et al., 2019). By comparing the genotype data of the diseased population and the control group, significant associations can be found between single nucleotide polymorphisms (SNPs) at certain gene loci and susceptibility to mastitis (Figure 2). These associated SNPs become potential genetic markers for disease resistance. Figure 2 SNP g.18174 A>G induces aberrant NCF4-TV splicing (Ju et al., 2015) Note: A: Schematic representation of the NCF4 mini-genes used in the functional splicing assay. The wild-type and mutant fragments contained 125 bp of intron 9 and 53 bp of exon 10; fragments harboring the A or G allele were separately cloned into the EcoRI and XhoI cloning sites of the pSPL3 vector; B: RT-PCR analysis of the NCF4 spliced transcripts on a 2% agarose gel. RT-PCR products were amplified from the total RNA of 293T cells transfected with the wild-type and mutant (g.18174 A>G) NCF4 mini-gene constructs. The size of the RT-PCR product (441 bp) corresponded to the amplified portion of intron 9 (77 bp), the retained portion of intron 9 (48 bp), the amplification of exon 10 (53 bp), and the pSPL3 control plasmid (263 bp). The size of the RT-PCR product (393 bp) corresponded to the amplified portion of intron 9 (77 bp), the amplification of exon 10 (53 bp), and the pSPL3 control plasmid (263 bp); C: Electrophoresis of RT-PCR products showing the presence and abundance of NCF4-TV transcript in bovine mammary samples with three NCF4 SNP g.18174 A>G genotypes. Expression of the NCF4-TV transcript is highest in mammary samples from GG animals, followed by those from AG and AA individuals
RkJQdWJsaXNoZXIy MjQ4ODYzMg==