CN-122012726-A - SNP molecular marker related to Tibetan sheep disease resistance, detection method and application thereof

Abstract

The invention provides an SNP molecular marker related to Tibetan sheep disease resistance, a detection method and application thereof, and belongs to the technical field of Tibetan sheep disease resistance detection, wherein the SNP molecular marker is positioned at 64702329 th base on chromosome 3 of international sheep reference genome oar_v4.0 version 3, the content of IL-1α, IL-6, TNF- α, TNF- β and IL-1Ra of Tibetan sheep individuals with GG molecular marker locus genotype is obviously lower than that of Tibetan sheep individuals with GA and AA genotype, and the content of IL-10 of Tibetan sheep individuals with AA genotype is obviously lower than that of Tibetan sheep individuals with GG genotype. According to the genotype of the SNP molecular marker locus, the content of key cytokines in Tibetan sheep individuals can be judged, and a new SNP molecular marker resource is provided for Tibetan sheep immune trait marker assisted selection.

Inventors

• LIU JIANBIN
• LU ZENGKUI
• YUAN CHAO
• GUO TINGTING
• CHEN BOWEN
• SONG YUFANG

Assignees

• 中国农业科学院兰州畜牧与兽药研究所

Dates

Publication Date

20260512

Application Date

20260128

Claims (6)

1. 1. A SNP molecular marker related to Tibetan sheep disease resistance is characterized in that the SNP molecular marker is positioned at 64702329 th base on chromosome 3 of an international sheep reference genome oar_v4.0 version 3, the mutation type is G/A, three genotypes of GG, GA and AA exist, the content of IL-1α, IL-6, TNF- α, TNF- β and IL-1Ra of Tibetan sheep individuals with GG molecular marker loci is obviously lower than that of Tibetan sheep individuals with GA and AA genotypes, and the content of IL-10 of Tibetan sheep individuals with AA genotypes is obviously lower than that of Tibetan sheep individuals with GG genotypes.
2. 2. A DNA molecule comprising the SNP molecular marker of claim 1, wherein the nucleotide sequence of the DNA molecule is shown in SEQ ID No. 1.
3. 3. The kit for detecting the genotype of the SNP molecular marker according to claim 1, which is characterized by comprising amplification primers and PCR reaction reagents.
4. 4. The kit of claim 3, wherein the amplification primers comprise an upstream primer as shown in SEQ ID NO.2 and a downstream primer as shown in SEQ ID NO. 3.
5. 5. A method for detecting the genotype of the SNP molecular marker as set forth in claim 1, characterized by comprising the steps of: 1) Extracting blood genome DNA of a sample to be detected; 2) Performing PCR amplification by using the genomic DNA obtained in the step 1) as a template and using the primer in the kit of claim 3 or 4 to obtain an amplification product; 3) Sequencing the amplified product, analyzing the genotype of 268 position of the amplified product, and determining the genotype of the SNP molecular marker.
6. 6. Use of the SNP molecular marker of claim 1, the DNA molecule of claim 2, the kit of claim 3 or 4 in the auxiliary breeding of Tibetan sheep disease resistance traits.

Description

SNP molecular marker related to Tibetan sheep disease resistance, detection method and application thereof Technical Field The invention belongs to the technical field of detection of disease resistance of Tibetan sheep, and particularly relates to an SNP molecular marker related to the disease resistance of Tibetan sheep, a detection method and application thereof. Background The Tibetan sheep is taken as a livestock genetic resource special for Qinghai-Tibet plateau, is suitable for extreme environments such as high cold, hypoxia, strong radiation and the like for a long time, forms unique stress resistance, and particularly shows remarkable advantages in disease resistance. The excavation and utilization of the disease-resistant genetic mechanism of Tibetan sheep has important significance for cultivating new varieties with strong disease resistance, reducing economic loss caused by diseases in animal husbandry and promoting green healthy cultivation. In livestock breeding, traditional disease resistance breeding mainly depends on phenotype recording (such as morbidity and mortality) and pathogen attack tests of individuals and their relatives. However, this method has inherent disadvantages of long cycle, high cost, low efficiency, and potential interference from environmental factors. More importantly, for some diseases with long latency or difficult to carry out artificial infection, the traditional breeding method is difficult to effectively implement. Disease resistance is essentially the ability of the immune system to recognize and clear pathogens, and cytokines serve as the core regulatory molecules of the immune response, closely related to the disease resistance phenotype. Interleukin 1 alpha (IL-1 alpha), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), tumor necrosis factor beta (TNF-beta), interleukin 1 receptor antagonist (IL-1 Ra) and interleukin 10 (IL-10) form a core regulation network for body inflammation and immune balance, and the proinflammatory factors IL-1 alpha, IL-6, TNF-alpha and TNF-beta can activate immune cells such as macrophages and T lymphocytes to start natural immune and adaptive immune reaction, effectively resist pathogen invasion, and the anti-inflammatory factors IL-1Ra and IL-10 can prevent tissue injury caused by uncontrolled immune reaction through inhibiting over-expression of the proinflammatory factors and maintain the immune steady state of the body. Research proves that the content level of the cytokines is obviously related to the disease resistance of livestock and poultry, and the genetic variation of the expression regulation is an important factor for determining the disease resistance potential of individuals. With the development of molecular biology, molecular Marker Assisted Selection (MAS) technology has brought revolutionary progress to livestock breeding. Among them, single Nucleotide Polymorphism (SNP) has become one of the most ideal molecular markers in current genetic breeding because of its wide distribution in genome, abundant quantity, high stability and easy realization of high-throughput automated detection. Through identifying SNP loci closely linked with important economic characters (including disease resistance), early and accurate breeding of the breeding stock can be realized, the breeding generation interval is greatly shortened, and the breeding efficiency is improved. At present, although some candidate genes or molecular markers related to livestock immune traits are reported in researches, the unique disease-resistant genetic basis of the Tibetan sheep is still not fully resolved. Particularly lacking are specific molecular markers that can directly and effectively indicate their overall immunomodulatory capacity and disease resistance potential. Disclosure of Invention In view of the above, the present invention aims to provide a SNP molecular marker related to Tibetan sheep disease resistance, a detection method and application thereof. Cytokines are the core mediators of immune regulation of the body, and the level of expression directly reflects the immune state and inflammatory response intensity of the body. The levels of these key cytokines (IL-1. Alpha., IL-6, TNF-alpha, TNF-beta, IL-1Ra, IL-10) in the blood are important phenotypic indicators for assessing immune homeostasis and disease resistance of an individual. The invention discovers SNP molecular markers which are obviously related to the content of the key cytokines, and can judge the content of IL-1 alpha, IL-6, TNF-alpha, TNF-beta, IL-1Ra and IL-10 of Tibetan sheep individuals by detecting the genotype of the SNP molecular marker loci. The invention provides an SNP molecular marker related to Tibetan sheep disease resistance, which is positioned at 64702329 th base on chromosome 3 of international sheep reference genome oar_v4.0 version 3, wherein the mutation type is G/A, the content of IL-1α, IL-6, TNF- α, TNF- β and IL-1Ra of Tibetan sheep in