CN111154891A

CN111154891A - Detection primer pair, kit, method and application of sheep IGF2BP1 gene insertion/deletion polymorphism

Info

Publication number: CN111154891A
Application number: CN202010083871.XA
Authority: CN
Inventors: 张清峰; 潘传英; 刘洪飞; 白洋洋; 林春建; 佐建明; 卢小芳; 蓝贤勇
Original assignee: Tianjin Aoqun Animal Husbandry Co ltd
Current assignee: Tianjin Aoqun Animal Husbandry Co ltd
Priority date: 2020-02-10
Filing date: 2020-02-10
Publication date: 2020-05-15
Anticipated expiration: 2040-02-10
Also published as: CN111154891B

Abstract

The invention relates to a method for detecting sheep IGF2BP1 gene insertion/deletion polymorphism, which comprises the following steps: taking the whole genome DNA of the sheep to be detected as a template, taking a primer pair as an amplification primer, amplifying a fragment containing the insertion/deletion polymorphic site in the downstream region of the sheep IGF2BP1 gene by using PCR, carrying out electrophoresis on a PCR amplification product, and identifying the genotype of the sheep individual to be detected at the insertion/deletion polymorphic site according to an electrophoresis result. The insertion/deletion polymorphic site detected by the invention can be used as a molecular genetic marker of the lamb characters, thereby accelerating the establishment of a sheep population with excellent lamb characters and improving the speed of fine breed breeding.

Description

Detection primer pair, kit, method and application of sheep IGF2BP1 gene insertion/deletion polymorphism

Technical Field

The invention belongs to the technical field of biotechnology and livestock breeding, and particularly relates to a detection primer pair, a kit, a method and application of sheep IGF2BP1 gene insertion/deletion polymorphism.

Background

With the development of economy and the high living standard of people, people tend to have meat foods with high nutrition and high quality. Sheep is an important meat food source, and has the characteristics of delicious meat, high protein, low fat and the like which are increasingly popular with people. Therefore, in order to improve the reproduction rate and the number of the sheep, the most important thing is to select and breed a good sheep variety with high yield. Nowadays, although the genetic breeding of animals still mainly adopts the traditional breeding method, with the further improvement of genetic maps of various species and the completion of genome sequencing work and the rapid development of molecular biology, the molecular breeding mode is combined with the traditional breeding method to solve the genetic breeding problem of animals. Among them, a method of screening an effective genetic marker to assist selective breeding through polymorphism studies of related genes has been widely accepted.

Although animal genetic breeding still involves quantitative genetics-based crossbreeding, a new molecular breeding mode, namely Marker-assisted selection (MAS) technology, emerges with the continuous improvement and development of sequencing technology. The technology can rapidly and accurately analyze the genetic composition of an individual by detecting a certain genetic marker at a molecular level, thereby realizing the direct selection of the genotype, greatly shortening the breeding period and greatly improving the accuracy of breeding. With the advent of sequencing technology, two new genetic markers, Single Nucleotide Polymorphisms (SNPs) and insertions/deletions (indels), also known as biallelic genetic markers, have been discovered because of their common presence of two alleles. Because of the insertion or deletion of the DNA fragment, the InDel genetic marker shows the length polymorphism of the DNA fragment and is widely distributed in the whole genome, and the mutation frequency is only second to that of the SNP. The InDel genetic markers are numerous, have the characteristics of STR and SNP genetic markers, and are widely applied to the fields of genetics, classification diagnosis, genetic map construction and the like.

With the intensive research of the whole genomics, a large number of InDel sites are found, and provide a large amount of biological information for theoretical research and genetic breeding application research. As a genetic marker, the gene is mostly focused on the genome research of human beings and various crops (such as rice, corn and the like), but the research and the application of functional genes of livestock, particularly InDel markers in breeding aspects related to the growth and reproduction traits of ruminants are few. Therefore, in the breeding target of breeding sheep with excellent lambing traits, the MAS is utilized to accelerate the establishment of sheep populations with excellent lambing traits by detecting the gene polymorphism of DNA markers which are screened to be closely related to the lambing traits on the DNA level and analyzing the association between the gene polymorphism and the lambing traits.

As one of binding protein genes of IGF2 (IGF2BPs), the sheep IGF2BP1 gene is located on chromosome 11, has 15 exons and 14 introns, is about 39.9kb in length, and can encode three protein subtypes. The IGF2BP1 gene (also known as IMP1, CRD-BP) is an important member of the IGF2BP family, which encodes an RNA binding protein, and structural studies of IGF2BP1 found that it contains six typical RNA binding domains, including four KH (K homology) domains and two RRMs (RNA recognition motifs). Its IGF2BP1 can bind via KH domain⁶A modifies mRNA molecules of IGF2, PTEN, ACTB, MAPK4, MKI67, c-MYC, CD44 and the like to maintain the stability of the mRNA molecules, and further influences the growth and proliferation of cells. In addition, it has been found that many mirnas and lncrnas can indirectly regulate the stability, translation ability and distribution region of target mRNA molecules by binding IGF2BP 1. IGF2BP1 is widely expressed in fetal tissues and in more than 16 tumor tissues, but only in a few normal adult tissues. Since it not only affects the growth and proliferation of cells, but alsoAnd can also promote the development of embryos, thereby having important significance in the mechanism research of the early embryo development process of human beings and animals. However, no published patent literature report that the InDel site of the IGF2BP1 gene has significant correlation with the sheep lambing trait is found at present.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a detection primer pair, a kit, a method and application of sheep IGF2BP1 gene insertion/deletion polymorphism.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a pair of detection primers for detecting an insertion/deletion polymorphism of a sheep IGF2BP1 gene, wherein the pair of detection primers is capable of amplifying a fragment comprising the insertion/deletion polymorphic site of an intron region of the sheep IGF2BP1 gene by PCR.

Furthermore, the insertion/deletion polymorphic site is a 5-BP insertion/deletion polymorphic site of sheep IGF2BP1 gene NC-019468.1: g.37056439& 37056440.

Moreover, the primer pair is:

an upstream primer: SEQ NO. 1;

a downstream primer: SEQ NO. 2.

The application of the detection primer pair for the sheep IGF2BP1 gene insertion/deletion polymorphism in sheep molecular marker-assisted selective breeding is provided.

The kit for detecting the sheep IGF2BP1 gene insertion/deletion polymorphism is used as a detection primer pair.

Moreover, the kit can use the genomic DNA of the sheep to be detected as a template, a primer pair as an amplification primer, amplify a fragment containing the insertion/deletion polymorphic site of the intron region of the sheep IGF2BP1 gene by using PCR (polymerase chain reaction), perform electrophoresis on an amplification product, and identify the genotype of the insertion/deletion polymorphic site according to an electrophoresis result.

A method for detecting sheep IGF2BP1 gene insertion/deletion polymorphism by using the detection primer pair comprises the following steps:

taking the whole genome DNA of the sheep to be detected as a template, taking a primer pair as an amplification primer, amplifying a fragment containing the insertion/deletion polymorphic site in the downstream region of the sheep IGF2BP1 gene by using PCR, carrying out electrophoresis on a PCR amplification product, and identifying the genotype of the sheep individual to be detected at the insertion/deletion polymorphic site according to an electrophoresis result.

Moreover, the reaction procedure adopted by the PCR is as follows: pre-denaturation at 95 ℃ for 5 min; denaturation at 94 ℃ for 30s, annealing at 60 ℃ for 30s, extension at 72 ℃ for 12s, and 14 cycles, wherein the annealing temperature is reduced by 1 ℃ after each cycle; annealing at 50 ℃ for 30s, extending at 72 ℃ for 12s, and performing 34 cycles; extending for 10min at 72 ℃;

or, agarose gel with mass concentration of 3.0% is adopted during electrophoresis.

Moreover, according to the electrophoresis result, the insertion/insertion genotype II of the insertion/deletion polymorphic site is represented by 107bp one stripe, the insertion/deletion genotype ID is represented by 107bp and 102bp two stripes, and the deletion/deletion genotype DD is represented by 102bp one stripe;

wherein the insertion/deletion ID genotype of the insertion/deletion polymorphic site can be used as a DNA marker for improving the second-fetus lamb characters of sheep.

The method for detecting sheep IGF2BP1 gene insertion/deletion polymorphism is applied to sheep molecular marker-assisted selective breeding.

The invention has the advantages and positive effects that:

1. according to the invention, a primer is designed according to the insertion/deletion polymorphic site (reference sequence NC-019468.1: g.37056439&37056440) in the downstream region of sheep IGF2BP1 gene, and the genotype of the insertion/deletion polymorphic site can be detected simply, rapidly, at low cost and accurately by sequence amplification and electrophoretic identification by using sheep genome DNA as a template.

2. The invention identifies the genotype and analyzes the gene frequency of the sheep (such as Australian white sheep) IGF2BP1 gene insertion/deletion polymorphic site (reference sequence NC-019468.1: g.37056439&37056440), and performs the correlation analysis of the genotype of the insertion/deletion polymorphic site and the sheep lambing character, and the result shows that the insertion/deletion polymorphic site detected by the invention can be used as the molecular genetic marker of the sheep lambing character, thereby accelerating the establishment of sheep population with excellent lambing character and improving the speed of fine breed breeding.

3. The invention relates to rapid and accurate typing detection of 5-BP insertion/deletion polymorphism (InDel) sites of IGF2BP1 related genes related to early embryo development, cell growth and proliferation in sheep and application thereof in molecular Marker Assisted Selection (MAS) breeding, in particular to a DNA detection method and a special kit for detecting the sheep lambing number by the assistance of IGF2BP1 gene, which can rapidly establish a sheep genetic resource population with excellent lambing property.

Drawings

FIG. 1 shows the result of agarose gel electrophoresis of the amplified product of sheep IGF2BP1 gene (primer pair P1) according to the invention; m represents Marker;

FIG. 2 is a sequence diagram of PCR amplification products of sheep IGF2BP1 gene according to the invention; wherein: the part marked by the black box represents the complement of the 5-bp insertion (GGAGA): NC-019468.1 g.37056439&37056440 insTCTCC; rs 594668996.

Detailed Description

The following detailed description of the embodiments of the present invention is provided for the purpose of illustration and not limitation, and should not be construed as limiting the scope of the invention.

The raw materials used in the invention are conventional commercial products unless otherwise specified; the methods used in the present invention are conventional in the art unless otherwise specified.

Preferably, the insertion/deletion polymorphic site is a sheep IGF2BP1 gene NC-019468.1: g.37056439&37056440 bit 5-BP insertion/deletion polymorphic site.

Preferably, the primer pair is:

an upstream primer: SEQ NO. 15 '-TTTTTCGGTTTGGGTCGTGGA-3' (21 nt);

a downstream primer: SEQ NO. 25 '-CGCAGGAAAGAGCAGAAGGTG-3' (21 nt).

Preferably, the kit can use the genomic DNA of the sheep to be detected as a template, a primer pair as an amplification primer, amplify a fragment containing the insertion/deletion polymorphic sites of the intron region of the sheep IGF2BP1 gene by using PCR (polymerase chain reaction), perform electrophoresis on an amplification product, and identify the genotype of the insertion/deletion polymorphic sites according to an electrophoresis result.

Preferably, the reaction procedure adopted by the PCR is as follows: pre-denaturation at 95 ℃ for 5 min; denaturation at 94 ℃ for 30s, annealing at 60 ℃ for 30s, extension at 72 ℃ for 12s, and 14 cycles, wherein the annealing temperature is reduced by 1 ℃ after each cycle; annealing at 50 ℃ for 30s, extending at 72 ℃ for 12s, and performing 34 cycles; extending for 10min at 72 ℃;

Preferably, according to the electrophoresis result, the insertion/insertion genotype II of the insertion/deletion polymorphic site is represented by 107bp one stripe, the insertion/deletion genotype ID is represented by 107bp and 102bp two stripes, and the deletion/deletion genotype DD is represented by 102bp one stripe;

More specifically, the preparation and detection are as follows:

the invention utilizes a PCR method to detect insertion/deletion polymorphism possibly generated by mutation of the downstream region (reference sequence: NC-019468.1) of sheep IGF2BP1 gene, and carries out correlation analysis on the polymorphism and sheep lambing traits to verify whether the polymorphism exists as a molecular marker for auxiliary selection in sheep molecular breeding.

1. Experimental drugs and reagents

1.1 Biochemical and biological reagents ① Taq DNA polymerase (available from Fermantas, MBI), ② proteinase K (available from Huamei bioengineering Co., Ltd.), ③ Marker I (available from Tiangen Biochemical technology, Beijing, Ltd.).

1.2 general reagents: tris, EDTA, NaCl, HCl, NaOH, Tris saturated phenol, chloroform, absolute ethyl alcohol, Sodium Dodecyl Sulfate (SDS), Ethidium Bromide (EB), bromophenol blue, dimethyl benzene cyanide FF, boric acid, agarose and the like, wherein common reagents are purchased from Huamei bioengineering company and are imported split charging products.

1.3 solution and buffer: all solutions and buffers were prepared using deionized ultrapure water. The autoclaving condition was 15bf/in (1.034X 10)²KPa), 25 min. The reagent preparation methods refer to molecular cloning experimental guidelines compiled by Sambrook et al;

1) solution for extracting tissue-like DNA

① 2mol/LNaCl 11.688g is dissolved in water, the volume is determined to be 100mL, and the autoclave is sterilized;

② tissue DNA extract (100mL), L mol/L Tris-HCl (pH8.0) L mL, 0.5mol/L EDTA (pH8.0)20mL, and 2mol/L NaCl 5mL, constant volume to 100 mL;

2) solutions for agarose gel electrophoresis analysis

① 0.5.5 × TBE buffer solution, taking 10 × TBE 50mL to fix the volume to 1000 mL;

② sample buffer solution containing bromophenol blue with final mass concentration of 0.25% and dimethylbenzene blue FF with final mass concentration of 0.25%, and the solvent is 40.0% (w/v) sucrose water solution.

2. Design of sheep IGF2BP1 gene InDel site amplification primer

The sequence of sheep IGF2BP1 gene (NC _019468.1) was searched at NCBI and primers capable of amplifying multiple candidate InDel site DNA fragments of IGF2BP1 gene were designed using Primer 5.0, wherein the PCR Primer pair capable of amplifying InDel site in the downstream region of sheep IGF2BP1 gene was P1 (Primer design completion time 2019 months). The sequences of the primer pair P1 are shown in Table 1.

TABLE 1 sheep IGF2BP1 Gene InDel site amplification primer Table

The sheep genome was amplified by the primer pair P1 described above, and a fragment containing a candidate In Del site (NC-019468.1: g.37056439&37056440) In the downstream region of sheep IGF2BP1 gene was amplified. Theoretically, when the sequence TCTCC in the downstream region g.37056439&37056440 of IGF2BP1 gene is deleted, 102BP band is obtained by PCR amplification of P1 by using primer pair; when the sequence TCTCC is present (inserted), the PCR amplification with the primer pair P1 results in a band with a size of 107 bp; when the sequence TCTCC had an insertion on one allele and a deletion on the other allele, PCR amplification with primer pair P1 resulted in bands of 107bp and 102bp in size, respectively.

3. PCR amplification of sheep IGF2BP1 gene fragment to be detected by primer pair P1

3.1 Collection of sheep tissue samples

The animals used in the experiment were 916 samples in total, and the specific information is shown in table 2. The lambing character data is measured by original seed field workers, individual tissue samples are taken, the samples are stored by 70% ethanol, and the ice boxes are brought back to a laboratory at low temperature and then are frozen at minus 80 ℃.

TABLE 2 sample information

3.2 extraction and isolation of genomic DNA from tissue samples

Reference is made to the molecular cloning guidelines (2002) compiled by Sambrook et al and to the following: lanxian warrior, genetic variation of important functional genes of goats and the relationship between the genetic variation and economic traits [ D. ] in doctor academic thesis of university of agriculture and forestry in northwest, 2007, Shaanxi Yangling.

3.3 agarose gel electrophoresis detection of DNA

Reference is made to the molecular cloning guidelines (2002) compiled by Sambrook et al.

3.4 purification of DNA

3.5 spectrophotometric detection of DNA

The OD values of the DNA samples at 260nm and 280nm were measured by an ultraviolet photometer. Calculation of DNA content and OD₂₆₀/OD₂₈₀The ratio of (a) to (b). Such as OD₂₆₀/OD₂₈₀The ratio is less than 1.6, which indicates that the sample contains more protein or phenol, and purification is required; if the ratio is greater than 1.8, then RNA purification removal should be considered.

DNA concentration (ng/. mu.L) ═ 50 XOD₂₆₀Value x dilution factor.

After the DNA detection, a certain amount of the DNA was taken out and diluted to 10 ng/. mu.L, and stored at-20 ℃ for later use, and the rest at-80 ℃.

3.6 PCR amplification

The PCR reaction system adopts a mixed sample adding method, namely the total amount of various reaction components is calculated according to the quantity of various components required by each reaction system and the quantity of PCR reaction required by 1 reaction, the reaction components are added into 1 1.5mL centrifuge tube, the centrifuge tubes are mixed fully and evenly and then are subjected to instantaneous centrifugation, the reaction components are subpackaged into 0.2mL Eppendorf PCR tubes, template DNA is added, and PCR amplification is carried out after the instantaneous centrifugation; the PCR reaction system comprises 6.5 mu L of 2 xTaq PCR Supermix (comprising Taq DNA polymerase, dNTPs and reaction buffer); upstream primer 0.5 μ L; 0.5. mu.L of downstream primer (10 pmol/. mu.L of upstream primer and downstream primer); 0.6. mu.L of genomic DNA (concentration of 10 ng/. mu.L of sheep genomic DNA); 4.9 mu L of deionized water; a total of 13. mu.L.

3.7 procedure for PCR reaction

Pre-denaturation at 95 ℃ for 5 min; denaturation at 94 ℃ for 30s, annealing at 60 ℃ for 30s, extension at 72 ℃ for 12s, and 14 cycles, wherein the annealing temperature is reduced by 1 ℃ after each cycle; annealing at 50 ℃ for 30s, extending at 72 ℃ for 12s, and performing 34 cycles; extension at 72 ℃ for 10 min.

4. Agarose gel electrophoresis detection analysis of amplified PCR products

Agarose gel electrophoresis detection is divided into 3 steps: 1) preparing 3% agarose gel, dyeing by using nucleic acid dye, spotting 6 mu L, and performing electrophoresis at 120V for 40-50 min after spotting; 2) when the DNA fragments with different molecular weights are clearly separated, imaging in a BIO-RAD GelDoc 2000 gel imaging system; 3) analyzing the polymorphism of the locus according to the agarose gel electrophoresis result;

for the 5-BP insertion/deletion polymorphism (5-bpInDel) site (NC-019468.1: g.37056439&37056440) existing in the downstream region of the Australian white sheep IGF2BP1 gene, the polymorphism analysis results of different sheep individuals are shown in figure 1, after the PCR amplification product (primer pair P1) is detected by agarose gel electrophoresis, the insertion/deletion genotype (II) of the amplified corresponding insertion/deletion polymorphism site shows 107BP one stripe, the insertion/deletion genotype (ID) shows 107BP and 102BP two stripes, and the deletion/deletion genotype (DD) shows 102BP one stripe. The results of the analysis were verified by sequencing (see figure 2).

5. Frequency statistical analysis of sheep IGF2BP1 gene InDel locus

1) Gene and genotype frequency

Genotype frequency refers to the ratio of the number of individuals with a certain genotype for a trait to the total number of individuals in a population. P_YY＝N_YYN, wherein P_YYRepresents the YY genotype frequency of a certain locus; n is a radical of_YYRepresenting the number of individuals in the population having a YY genotype; and N is the total number of detection groups.

Gene frequency refers to the relative ratio of a given gene number to the total number of alleles in a populationA ratio. The formula for the calculation can be written as: p_Y＝(2N_YY+N_Ya1+N_Ya2+N_Ya3+N_Ya4+……+N_Yan)/2N

In the formula, P_YIndicating allele Y frequency, N_YYRepresenting the number of individuals in the population having the YY genotype, N_YaiRepresenting the number of individuals having Yai genotype in the population, a 1-an are n different multiple alleles of allele Y.

2) Statistical results

The genotype frequencies and allele frequencies of the 5-BP insertion/deletion polymorphic sites of the Australian white sheep IGF2BP1 gene are shown in Table 3.

TABLE 3 sheep IGF2BP1 Gene frequency distribution Table at InDel site

6. Association analysis of sheep IGF2BP1 gene InDel site gene effect

Genotype data: carrying out agarose gel electrophoresis on the genotype identified after PCR amplification;

production data: lambing data for Australian white sheep.

And (3) correlation analysis model: the SPSS (23.0) software was used to analyze the association of genotypes with lambing traits in this breed. The resulting data is first analyzed descriptively by statistics to determine if outliers exist. The effect of the genotype is then further analyzed using analysis of variance, multivariate linear models, or chi-square analysis based on the characteristics of the data. During the data processing, a fixed model is used for correlation analysis in consideration of the individual effects, the interaction between genes and the genotype effects. Furthermore, the trade-off is made according to actual conditions, and the complete model: y is_ijklm＝μ+S_i+HYS_j+G_l+e_ijlm(ii) a Wherein, Y_ijklm: recording the number of lambs born by the individual; μ: an overall mean; s_i: population means with different offspring types; HYS_j: the fetal secondary effect; g_l: the fixing effect of the genotype; e.g. of the type_ijlm: random error. The second few fetuses resulted from the small number of II genotypes (n)<5) Thus, a t-test was performed, and the correlation analysis results are shown in Table 4.

TABLE 4 analysis of association between sheep IGF2BP1 gene InDel locus and Australian white lambing number trait (analysis of variance)

Note: the difference in the letters on the shoulder of the mean values indicates significant difference; note that: II is 0 and N <3, so no analysis is carried out.

Meanwhile, the number of lambs in the second fetus and the genotype of the locus are subjected to independent chi square (chi square)²) The results of the examination are shown in Table 5.

TABLE 5 analysis of association between sheep IGF2BP1 gene InDel locus and number of lambs in Australian white (chi fang test)

Note that: II is 0 and N <3, so no analysis is carried out.

As can be seen from tables 4 and 5, in the study of the lambing characteristics of Australian white sheep, the 5-bpInDel polymorphism of IGF2BP1 gene had a very significant effect on the number of lambs in the second-generation Australian white sheep (P < 0.01). Wherein, the ID genotype individual lambing property is superior to that of the DD genotype individual. Therefore, the ID genotype of the sheep IGF2BP1 gene 5-BP insertion/deletion polymorphic site (NC-019468.1: g.37056439&37056440) can be used as a DNA molecular marker for the number of lambs born by sheep in the second fetus.

In a word, the invention detects the genotype of the sheep IGF2BP1 gene 5-BP insertion/deletion polymorphic site (NC-019468.1: g.37056439&37056440) by using a PCR amplification method, and performs correlation analysis on the genotype and the lambing property of Australian white sheep to find a molecular marker which can be used as an auxiliary selection in sheep molecular breeding, thereby accelerating the speed of fine breed breeding. The detection method of sheep IGF2BP1 gene insertion/deletion polymorphism established by the invention provides theoretical and practical basis for marker-assisted selection (MAS) application of sheep lambing traits by using InDel.

The related sequences of the invention are as follows:

1. artificially synthesized SEQ NO.1

tttttcggtt tgggtcgtgg a 21

2. Artificially synthesized SEQ NO.2

cgcaggaaag agcagaaggt g 21

3. NC-019468.1 g.37056439&37056440 bit insertion sequence

tctcc 5

Although the embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that: various substitutions, changes and modifications are possible without departing from the spirit and scope of the invention and the appended claims, and therefore the scope of the invention is not limited to the embodiments disclosed.

Sequence listing

<110> Tianjin Olympic group animal husbandry Co., Ltd

<120> sheep IGF2BP1 gene insertion/deletion polymorphism detection primer pair, kit, method and application

<160>3

<170>SIPOSequenceListing 1.0

<210>1

<211>21

<212>DNA

<213> upstream primer (Unknown)

<400>1

tttttcggtt tgggtcgtgg a 21

<210>2

<211>21

<212>DNA

<213> downstream primer (Unknown)

<400>2

cgcaggaaag agcagaaggt g 21

<210>3

<211>5

<212>DNA

<213> NC-019468.1: g.37056439&37056440 bit insertion sequence (Unknown)

<400>3

tctcc 5

Claims

1. A detection primer pair for sheep IGF2BP1 gene insertion/deletion polymorphism is characterized in that: the detection primer pair can amplify a fragment containing the polymorphic site of the insertion/deletion of the intron region of the sheep IGF2BP1 gene by PCR.

2. The pair of primers for detecting an insertion/deletion polymorphism of sheep IGF2BP1 gene according to claim 1, wherein: the insertion/deletion polymorphic site is a 5-BP insertion/deletion polymorphic site of sheep IGF2BP1 gene NC-019468.1: g.37056439& 37056440.

3. The pair of primers for detecting an insertion/deletion polymorphism of sheep IGF2BP1 gene according to claim 1 or 2, wherein: the primer pair is as follows:

an upstream primer: SEQ NO. 1;

a downstream primer: SEQ NO. 2.

4. Use of a pair of primers for detecting an insertion/deletion polymorphism of sheep IGF2BP1 gene according to any one of claims 1 to 3 in sheep molecular marker assisted selective breeding.

5. A special detection kit for detecting an sheep IGF2BP1 gene insertion/deletion polymorphism using the primer set according to any one of claims 1 to 3.

6. The dedicated detection kit according to claim 5, characterized in that: the kit can use the genomic DNA of the sheep to be detected as a template, a primer pair as an amplification primer, amplify a fragment containing the insertion/deletion polymorphic sites of the intron region of the sheep IGF2BP1 gene by using PCR, perform electrophoresis on an amplification product, and identify the genotype of the insertion/deletion polymorphic sites according to an electrophoresis result.

7. A method for detecting an sheep IGF2BP1 gene insertion/deletion polymorphism using a pair of detection primers as set forth in any one of claims 1 to 3, characterized in that: the method comprises the following steps:

8. The method for detecting sheep IGF2BP1 gene insertion/deletion polymorphism according to claim 7, wherein: the reaction procedure adopted by the PCR is as follows: pre-denaturation at 95 ℃ for 5 min; denaturation at 94 ℃ for 30s, annealing at 60 ℃ for 30s, extension at 72 ℃ for 12s, and 14 cycles, wherein the annealing temperature is reduced by 1 ℃ after each cycle; annealing at 50 ℃ for 30s, extending at 72 ℃ for 12s, and performing 34 cycles; extending for 10min at 72 ℃;

9. The method for detecting the sheep IGF2BP1 gene insertion/deletion polymorphism according to claim 7 or 8, wherein: according to the electrophoresis result, the insertion/insertion genotype II of the insertion/deletion polymorphic site is expressed as 107bp one stripe, the insertion/deletion genotype ID is expressed as 107bp and 102bp two stripes, and the deletion/deletion genotype DD is expressed as 102bp one stripe;

10. Use of a method for detecting sheep IGF2BP1 gene insertion/deletion polymorphism according to any one of claims 7 to 9 in sheep molecular marker assisted selective breeding.