Application of SNP (Single Nucleotide Polymorphism) molecular marker in identification or auxiliary identification of breast width of goat

Abstract

The invention relates to the field of molecular markers, in particular to application of an SNP (Single Nucleotide Polymorphism) molecular marker in identification or auxiliary identification of breast width of a goat. The invention provides an SNP (Single Nucleotide Polymorphism) molecular marker related to a goat chest breadth character. The SNP molecular marker comprises SNP01, SNP02, SNP03 and SNP04; wherein the SNP01 is a harmful mutation, and the significant dominant genotype is GG; sNP02 is a favorable mutation, and a remarkable dominant genotype is AA; sNP03 is beneficial mutation, and a remarkable dominant genotype is TT; sNP04 is a harmful mutation, and the significant dominant genotype is AA. The SNP molecular marker provided by the invention is related to the breast breadth character of the goat, and the breast breadth character of the goat can be more accurately predicted, so that effective selection is performed in the breeding process, the breeding efficiency of the goat with wider breast breadth is improved, and a new molecular marker resource is also provided for genetic breeding of other livestock.

Description

Technical Field

[0001] The present invention relates to the field of molecular markers, and particularly to the application of SNP molecular markers in identifying or assisting in identifying the chest width of goats. Background Art

[0002] As one of the important livestock, goats have rich germplasm resources globally. The chest width trait of goats is one of the important indicators to measure their production performance, which is directly related to the growth rate and meat quality of goats. In the field of goat genetic breeding, the improvement of chest width trait is of great significance for enhancing the economic value and production efficiency of goats. Traditional breeding methods mainly rely on phenotypic selection, but this method is inefficient and difficult to accurately predict the phenotypes of offspring. Molecular marker technology, especially single nucleotide polymorphism (SNP) loci, has become an important tool for identifying molecular markers related to complex traits. SNP loci are polymorphisms of DNA sequences caused by single nucleotide variations. They are densely distributed in the genome and carry huge amounts of genetic information, and are considered to be genetic markers with the best application prospects. However, there are currently no molecular markers related to the chest width of goats. Summary of the Invention

[0003] To solve the above problems, the present invention provides the application of SNP molecular markers in identifying or assisting in identifying the chest width of goats. The SNP molecular markers provided by the present invention can quickly screen and identify the chest width traits of 3-month-old goats and / or 9-month-old goats, and improve the breeding efficiency of goats with larger chest widths.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention provides the application of SNP molecular markers in identifying or assisting in identifying the chest width of goats, and the SNP molecular markers include: one or more of SNP01, SNP02, SNP03, and SNP04; SNP01 and SNP02 are related to the chest width of 3-month-old goats; SNP03 and SNP04 are related to the chest width of 9-month-old goats;

[0006] SNP01 is located at position 49851856 bp on chromosome 7 of the goat reference genome ARS1.2, the base is G or C, and the chest width of goats with the genotype GG is greater than that of goats with the genotype CC or GC;

[0007] SNP02 is located at position 38696821 bp on chromosome 11 of the goat reference genome ARS1.2, the base is G or A, and the chest width of goats with the genotype AA is greater than that of goats with the genotype GG or AG;

[0008] The SNP03 is located at 67007587bp of chromosome 18 of the goat reference genome ARS1.2, and the base is C or T. The chest width of goats with genotype TT is greater than the chest width of goats with genotype CC or TC.

[0009] The SNP04 is located at 42918187bp of chromosome 19 of the goat reference genome ARS1.2, and the base is A or C. The chest width of goats with genotype AA is greater than the chest width of goats with genotype CC or AC.

[0010] The RefSeq number of the goat reference genome ARS1.2 in the NCBI database is GCA_001704415.2.

[0011] The present invention provides a SNP molecular marker associated with the chest width trait of goats, including: one or more of SNP01, SNP02, SNP03 and SNP04;

[0012] The nucleotide sequence of SNP01 is shown in SEQ ID NO.1 or SEQ ID NO.2;

[0013] The nucleotide sequence of SNP02 is shown in SEQ ID NO.3 or SEQ ID NO.4;

[0014] The nucleotide sequence of SNP03 is shown in SEQ ID NO.5 or SEQ ID NO.6;

[0015] The nucleotide sequence of SNP04 is shown as SEQ ID NO.7 or SEQ ID NO.8.

[0016] The present invention provides the use of the SNP molecular marker described in the above technical solution in one or more of the following:

[0017] (1) Identify or assist in identifying the chest width of goats; (2) Select or assist in selecting goats with large chest width; (3) Cultivate or assist in cultivating goats with large chest width.

[0018] Preferably, the goats include 3-month-old goats and / or 9-month-old goats.

[0019] Preferably, the breed of goats includes Longling Yellow Goats.

[0020] The present invention provides a method for identifying or assisting in identifying the chest width of a goat, comprising the following steps:

[0021] Detecting the SNP molecular markers described in the above technical solution of the goat to be tested;

[0022] When the goat to be tested is a 3-month-old goat, if the base at the 101st position from the 5' end of the SNP01 is G, it is identified as a goat with a wide chest; if the base at the 101st position from the 5' end of the SNP01 is C, it is identified as a goat with a narrow chest;

[0023] When the goat to be tested is a 3-month-old goat, if the base at the 101st position from the 5' end of the SNP02 is A, it is identified as a goat with a wide chest; if the base at the 101st position from the 5' end of the SNP02 is G, it is identified as a goat with a narrow chest;

[0024] When the goat to be tested is a 9-month-old goat, if the base at the 101st position from the 5' end of the SNP03 is T, it is identified as a goat with a wide chest; if the base at the 101st position from the 5' end of the SNP03 is C, it is identified as a goat with a narrow chest;

[0025] When the goat to be tested is a 9-month-old goat, if the base at the 101st position from the 5' end of the SNP04 is A, it is identified as a goat with a wide chest; if the base at the 101st position from the 5' end of the SNP04 is C, it is identified as a goat with a narrow chest.

[0026] Preferably, the breed of the goat includes Longling Huangshan goat.

[0027] The present invention provides a method for screening or assisting in screening goats with a large chest width, including the following steps:

[0028] Detect the polymorphism of the SNP molecular marker described in the above technical solution of the goat to be tested;

[0029] Select and retain the goats carrying the GG genotype at the 101st position from the 5' end of the SNP01;

[0030] Select and retain the goats carrying the AA genotype at the 101st position from the 5' end of the SNP02;

[0031] Select and retain the goats carrying the TT genotype at the 101st position from the 5' end of the SNP03;

[0032] Select and retain the goats carrying the AA genotype at the 101st position from the 5' end of the SNP04.

[0033] Preferably, the breed of the goat includes Longling Huangshan goat.

[0034] The present invention provides a method for breeding or assisting in breeding goats with a large chest width by using the method described in the above technical solution, including the following steps:

[0035] Use the selected and retained goats as male or female parents for breeding, and select and retain the individuals with relatively more corresponding genotypes in the offspring according to the selection method in the method described in the above technical solution.

[0036] Beneficial effects:

[0037] Through genome-wide association study, the present invention screens out SNP loci significantly associated with the chest width trait of goats and obtains the molecular markers described in the above technical solution, which can more accurately predict the chest width trait of goats. As Figure 3 shown, the dominant genotype of SNP01 is GG; the dominant genotype of SNP02 is AA; the dominant genotype of SNP03 is TT; the dominant genotype of SNP04 is AA. The present invention not only provides technical support for the molecular breeding of goats, but also improves the efficiency of goat genetic improvement, and also provides new molecular marker resources for the genetic breeding of other livestock. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments.

[0039] Figure 1 are the Manhattan plot and QQ plot of the chest width trait of 3-month-old goats;

[0040] Figure 2 are the Manhattan plot and QQ plot of the chest width trait of 9-month-old goats;

[0041] Figure 3 are the results of the association analysis between the genotypes of the SNP combination (SNP01, SNP02, SNP03 and SNP04) and the chest width trait; where ns indicates no significant difference, * indicates P < 0.05, ** indicates P < 0.01, *** indicates P < 0.001, and **** indicates P < 0.0001. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] The present invention provides the application of SNP molecular markers in identifying or assisting in identifying the chest width of goats. The SNP molecular markers include one or more of SNP01, SNP02, SNP03 and SNP04; SNP01 and SNP02 are related to the chest width of 3-month-old goats; SNP03 and SNP04 are related to the chest width of 9-month-old goats;

[0043] SNP01 is located at position 49,851,856 bp on chromosome 7 of the goat reference genome ARS1.2, the base is G or C, and the chest width of goats with the genotype GG is greater than that of goats with the genotype CC or GC;

[0044] SNP02 is located at position 38,696,821 bp on chromosome 11 of the goat reference genome ARS1.2, the base is G or A, and the chest width of goats with the genotype AA is greater than that of goats with the genotype GG or AG;

[0045] The SNP03 is located at position 67007587 bp on chromosome 18 of the goat reference genome ARS1.2, with the base being C or T. The chest width of goats with the genotype TT is greater than that of goats with the genotype CC or TC.

[0046] The SNP04 is located at position 42918187 bp on chromosome 19 of the goat reference genome ARS1.2, with the base being A or C. The chest width of goats with the genotype AA is greater than that of goats with the genotype CC or AC.

[0047] The RefSeq number of the goat reference genome ARS1.2 in the NCBI database is GCA_001704415.2.

[0048] Through genome-wide association analysis, the present invention screens out SNP loci significantly associated with the chest width trait of goats and obtains the molecular markers described in the above technical solution, which can more accurately predict the chest width trait of goats. As Figure 3 shown, the dominant genotype of SNP01 is GG; the dominant genotype of SNP02 is AA; the dominant genotype of SNP03 is TT; the dominant genotype of SNP04 is AA. The present invention not only provides technical support for the molecular breeding of goats, but also improves the efficiency of goat genetic improvement, and also provides new molecular marker resources for the genetic breeding of other livestock.

[0049] Based on the above advantages, the present invention provides an SNP molecular marker related to the chest width trait of goats, including: one or more of SNP01, SNP02, SNP03, and SNP04;

[0050] The nucleotide sequence of the SNP01 is as shown in SEQ ID NO.1 or SEQ ID NO.2;

[0051] The nucleotide sequence of the SNP02 is as shown in SEQ ID NO.3 or SEQ ID NO.4;

[0052] The nucleotide sequence of the SNP03 is as shown in SEQ ID NO.5 or SEQ ID NO.6;

[0053] The nucleotide sequence of the SNP04 is as shown in SEQ ID NO.7 or SEQ ID NO.8.

[0054] The SNP molecular marker related to the chest width trait of goats provided by the present invention is a nucleic acid molecule (nucleotide sequence) containing the SNP locus intercepted according to the positioning of the SNP locus in the goat reference genome ARS1.2, and can be used to identify or assist in identifying the chest width of goats, screen or assist in screening goats with large chest widths, and breed or assist in breeding goats with large chest widths. Those skilled in the art can also intercept other sequences as SNP molecular markers according to the positioning information of the SNP locus in the SNP molecular marker described in the above technical solution in the goat reference genome ARS1.2, which also belongs to the protection scope of the present invention.

[0055] Based on the above advantages, the present invention provides the application of the SNP molecular marker described in the above technical solution in one or more of the following:

[0056] (1) Identifying or assisting in identifying the chest width of goats; (2) Screening or assisting in screening goats with large chest widths; (3) Breeding or assisting in breeding goats with large chest widths.

[0057] As an implementation method, the goats include 3-month-old goats and / or 9-month-old goats.

[0058] As an implementation method, the breed of the goats includes Longling Huangshan goats.

[0059] Based on the above advantages, the present invention provides a method for identifying or assisting in identifying the chest width of goats, including the following steps:

[0060] Detecting the SNP molecular marker described in the above technical solution of the goat to be tested;

[0061] When the goat to be tested is a 3-month-old goat, when the 101st base from the 5' end of the SNP01 is G, it is identified as a goat with a large chest width, and when the 101st base from the 5' end of the SNP01 is C, it is identified as a goat with a small chest width;

[0062] When the goat to be tested is a 3-month-old goat, when the 101st base from the 5' end of the SNP02 is A, it is identified as a goat with a large chest width, and when the 101st base from the 5' end of the SNP02 is G, it is identified as a goat with a small chest width;

[0063] When the goat to be tested is a 9-month-old goat, when the 101st base from the 5' end of the SNP03 is T, it is identified as a goat with a large chest width, and when the 101st base from the 5' end of the SNP03 is C, it is identified as a goat with a small chest width;

[0064] When the goat to be tested is a 9-month-old goat, when the 101st base from the 5' end of the SNP04 is A, it is identified as a goat with a large chest width, and when the 101st base from the 5' end of the SNP04 is C, it is identified as a goat with a small chest width.

[0065] As an implementation manner, the breed of the goats includes Longling Huangshan goats.

[0066] Based on the above advantages, the present invention provides a method for screening or assisting in screening goats with large chest width, comprising the following steps:

[0067] Detect the polymorphism of the SNP molecular markers described in the above technical solution of the to-be-detected goats;

[0068] Select and retain the goats carrying the GG genotype at the 101st position from the 5'-end of the SNP01;

[0069] Select and retain the goats carrying the AA genotype at the 101st position from the 5'-end of the SNP02;

[0070] Select and retain the goats carrying the TT genotype at the 101st position from the 5'-end of the SNP03;

[0071] Select and retain the goats carrying the AA genotype at the 101st position from the 5'-end of the SNP04.

[0072] As an implementation manner, the breed of the goats includes Longling Huangshan goats.

[0073] Based on the above advantages, the present invention provides a method for cultivating or assisting in cultivating goats with large chest width by using the method described in the above technical solution, comprising the following steps:

[0074] Use the selected and retained goats as male parents or female parents for breeding, and select and retain the individuals with relatively more corresponding genotypes in the offspring according to the selection method in the method described in the above technical solution.

[0075] The method provided by the present invention can increase the frequency of the advantageous genotypes generation by generation, thereby cultivating goats with more advantageous genotypes, and further cultivating goat breeds with larger chest width. Compared with screening according to phenotypes, the method provided by the present invention can perform screening according to the detection results of genotypes at 3-month-old goats and / or 9-month-old goats, improving the breeding efficiency of goats with larger chest width.

[0076] To further illustrate the present invention, the application of the SNP molecular markers provided by the present invention in identifying or assisting in identifying the chest width size of goats will be described in detail below in conjunction with the drawings and embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0077] Example 1 Screening of SNP Loci Related to Chest Width Trait of Goats

[0078] 1. Sample Collection and Sequencing

[0079] Collect 300 blood samples of Longling Huangshan goats and entrust Beijing Yinuozhongda Biotechnology Co., Ltd. to conduct whole-genome resequencing. Using high-throughput sequencing technology, obtain the genomic data of each sample. At the same time, strictly measure the chest width index of Longling Huangshan goats in accordance with NY / T 1236-2023 "Technical Specification for Determination of Production Performance of Breeding Goats".

[0080] 2. Data alignment and SNP locus identification

[0081] In the present invention, the Fastq files returned by the sequencing company are aligned with the ARS1.2 reference genome through the BWA (Version: 0.7.18) software. After alignment, the samtools (Version: 1.20) software is used to generate a bam format file. Then, a VCF file containing all variant information is obtained through the GATK (Version: 4.6.0.0) software. Finally, the VCF file is filtered through the Plink software to remove loci with a missing rate above 20% and a minor allele frequency within 0.05, and finally a SNP set containing 10,726,542 variant loci is obtained.

[0082] 3. Genome-wide association study

[0083] In the present invention, the emmax software is used to conduct a genome-wide association study on the chest width traits of these 300 goats at 3 months and 9 months of age respectively to identify SNP loci significantly associated with the chest width traits. SNP loci with a P (p-value) less than or equal to 0.000001 are screened out. The Manhattan plot and QQ plot of the chest circumference trait of goats at 3 months of age are shown in Figure 1 , and the Manhattan plot and QQ plot of the chest circumference trait of goats at 9 months of age are shown in Figure 2 .

[0084] In this embodiment, the specific process of the above software analysis is not specifically limited, and the above results can be obtained by using the above software based on the conventional operations of those skilled in the art.

[0085] 4. Extraction of SNP locus combinations

[0086] As shown in Table 1, SNP loci with a P value less than or equal to 0.000001 are extracted from the total SNP set to form 3 SNP loci related to the chest width trait of Longling Huangshan goats at 3 months of age.

[0087] SNP loci with a P value less than or equal to 0.000001 are extracted from the total SNP set to form 8 SNP loci related to the chest width trait of Longling Huangshan goats at 9 months of age.

[0088] Table 1 Significant SNP loci related to chest width trait

[0089]

[0090] Note: E in Table 1 is the symbol in scientific notation, representing 10 to the power of n. That is, 8.32E-07 in Table 1 is 8.32×10 -7 , and the same applies to other p-value values.

[0091] 5. Dominant genotype combinations

[0092] Perform a significance analysis on the phenotypic values corresponding to the genotypes of the selected significant SNPs, and screen out that there are dominant genotypes for SNP01, SNP02, SNP03, and SNP04. The statistical results are shown in Table 2. Finally, it is found that the dominant genotype of SNP01 is GG; the dominant genotype of SNP02 is AA; the dominant genotype of SNP03 is TT; the dominant genotype of SNP04 is AA.

[0093] Table 2 Information on SNP locus combinations screened in the present invention

[0094]

[0095] Note: E in Table 2 is the symbol in scientific notation, representing 10 to the power of n. That is, 8.32E-07 in Table 1 is 8.32×10 -7 , and the same applies to other p-value values.

[0096] The nucleotide sequences of the molecular markers containing the above mutation sites are shown in the table.

[0097] Table 3 Nucleotide sequences of SNP molecular markers screened in the present invention

[0098]

[0099]

[0100] It can be seen from the results in Example 1 that through resequencing and genome-wide association analysis, the present invention screens out significant SNP loci related to the chest width trait of goats, and excavates SNP01, SNP02, SNP03, and SNP04 loci and their dominant genotypes, which can more accurately predict the chest width trait of goats.

[0101] Example 2 SNP molecular marker detection and its association verification with chest width trait

[0102] Based on the SNP locus combinations (SNP01, SNP02, SNP03, and SNP04) obtained in Example 1, in this example, another 300 Longling Huangshan goats with body size traits at different growth and development stages were selected as the research objects, and genotyping was performed on the above 4 loci respectively, and an association analysis was carried out with the chest width of Longling Huangshan goats. The results are shown in Table 4 and Figure 3 as shown.

[0103] Table 4 Results of the association analysis between the polymorphism of SNP molecular markers screened in this invention and chest width traits

[0104]

[0105]

[0106] Note: Different letters indicate significant differences (P < 0.05), and the same letter indicates no significant difference (P > 0.05). If only one individual is detected for a certain genotype of the molecular marker, it is not included in the analysis.

[0107] As can be seen from Table 4, for individuals with the genotype GG, SNP01 has the largest chest width, while for individuals with the genotype CC, it has the smallest chest width; for individuals with the genotype AA, SNP02 has the largest chest width, while for individuals with the genotype GG, it has the smallest chest width; for individuals with the genotype TT, SNP03 has the largest chest width, while for individuals with the genotype CC, it has the smallest chest width; for individuals with the genotype AA, SNP04 has the largest chest width, while for individuals with the genotype CC, it has the smallest chest width.

[0108] In the genome-wide association study, the SNP01, SNP02, SNP03, and SNP04 molecular markers in the goat genome all reached the genome-wide significant level, indicating that these markers are significantly associated with the chest width traits of Longling Yellow Goats. Moreover, when the polymorphism at the 101st position from the 5' end of the SNP01 marker is G, it is beneficial for Longling Yellow Goats to have a larger chest width; when the polymorphism at the 101st position from the 5' end of the SNP02 marker is A, it is beneficial for Longling Yellow Goats to have a larger chest width; when the polymorphism at the 101st position from the 5' end of the SNP03 marker is T, it is beneficial for Longling Yellow Goats to have a larger chest width; when the polymorphism at the 101st position from the 5' end of the SNP04 marker is A, it is beneficial for Longling Yellow Goats to have a larger chest width.

[0109] Therefore, it can be seen that the Longling Huangshan goat breed with broad chest can be bred through SNP01, i.e., the G→C mutation at the 49,851,856th bp of chromosome 7 in the goat genome. By selecting individuals with the GG genotype as the male or female parent, the chest width of the offspring can be increased; the Longling Huangshan goat breed with broad chest can be bred through SNP02, i.e., the G→A mutation at the 38,696,821st bp of chromosome 11 in the goat genome. By selecting individuals with the AA genotype as the male or female parent, the chest width of the offspring can be increased; the Longling Huangshan goat breed with broad chest can be bred through SNP03, i.e., the C→T mutation at the 67,007,587th bp of chromosome 18 in the goat genome. By selecting individuals with the TT genotype as the male or female parent, the chest width of the offspring can be increased; the Longling Huangshan goat breed with broad chest can be bred through SNP04, i.e., the A→C mutation at the 42,918,187th bp of chromosome 19 in the goat genome. By selecting individuals with the AA genotype as the male or female parent, the chest width of the offspring can be increased.

[0110] Those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims

1. Application of SNP molecular markers in identifying or assisting in identifying the chest width of goats, characterized in that, The SNP molecular markers include: one or more of SNP01, SNP02, SNP03 and SNP04; SNP01 and SNP02 are related to the chest width of 3-month-old goats; SNP03 and SNP04 are related to the chest width of 9-month-old goats; The SNP01 is located at 49851856bp of chromosome 7 of the goat reference genome ARS1.2, and the base is G or C. The chest width of goats with a genotype of GG is greater than the chest width of goats with a genotype of CC or GC. The SNP02 is located at 38696821bp of chromosome 11 of the goat reference genome ARS1.2, and the base is G or A. The chest width of goats with genotype AA is greater than the chest width of goats with genotype GG or AG. The SNP03 is located at 67007587bp of chromosome 18 of the goat reference genome ARS1.2, and the base is C or T. The chest width of goats with genotype TT is greater than the chest width of goats with genotype CC or TC. The SNP04 is located at 42918187bp of chromosome 19 of the goat reference genome ARS1.2, and the base is A or C. The chest width of goats with genotype AA is greater than the chest width of goats with genotype CC or AC. The RefSeq number of the goat reference genome ARS1.2 in the NCBI database is GCA_001704415.

2.

2. A SNP molecular marker related to the chest width trait of goats, characterized in that, include: One or more of SNP01, SNP02, SNP03 and SNP04; The nucleotide sequence of SNP01 is shown in SEQ ID NO.1 or SEQ ID NO.2; The nucleotide sequence of SNP02 is shown in SEQ ID NO.3 or SEQ ID NO.4; The nucleotide sequence of SNP03 is shown in SEQ ID NO.5 or SEQ ID NO.6; The nucleotide sequence of SNP04 is shown as SEQ ID NO.7 or SEQ ID NO.

8.

3. Use of the SNP molecular marker according to claim 2 in one or more of the following: (1) Identify or assist in identifying the chest width of goats; (2) Select or assist in selecting goats with large chest width; (3) Cultivate or assist in cultivating goats with large chest width.

4. The application according to claim 3, wherein The goats include 3-month-old goats and / or 9-month-old goats.

5. The application according to claim 3 or 4, characterized in that, The breeds of goats include Longling yellow goats.

6. A method for identifying or assisting in the identification of the chest width of goats, characterized in that, The following steps are involved: Detecting the SNP molecular marker of claim 2 in the goat to be tested; When the goat to be tested is a 3-month-old goat, when the 101st base from the 5' end of SNP01 is G, the goat is identified as having a large chest width, and when the 101st base from the 5' end of SNP01 is C, the goat is identified as having a small chest width; When the goat to be tested is a 3-month-old goat, when the 101st base from the 5' end of SNP02 is A, the goat is identified as having a large chest width, and when the 101st base from the 5' end of SNP02 is G, the goat is identified as having a small chest width; When the goat to be tested is a 9-month-old goat, if the base at the 101st position from the 5' end of the SNP03 is T, it is identified as a goat with a broad chest; if the base at the 101st position from the 5' end of the SNP03 is C, it is identified as a goat with a narrow chest. When the goat to be tested is a 9-month-old goat, if the base at the 101st position from the 5' end of the SNP04 is A, it is identified as a goat with a broad chest; if the base at the 101st position from the 5' end of the SNP04 is C, it is identified as a goat with a narrow chest.

7. The method according to claim 6, characterized in that, The breed of the goat includes Longling Yellow Goat.

8. A method for screening or assisting in screening goats with a large chest width, characterized in that, It includes the following steps: Detect the polymorphism of the SNP molecular marker described in claim 2 of the goat to be tested; Select and retain the goats carrying the GG genotype at the 101st position from the 5' end of the SNP01; Select and retain the goats carrying the AA genotype at the 101st position from the 5' end of the SNP02; Select and retain the goats carrying the TT genotype at the 101st position from the 5' end of the SNP03; Select and retain the goats carrying the AA genotype at the 101st position from the 5' end of the SNP04.

9. The method according to claim 8, characterized in that, The breed of the goat includes Longling Yellow Goat.

10. A method for cultivating or assisting in cultivating goats with a large chest width by using the method described in claim 8 or 9, characterized in that, It includes the following steps: Use the selected and retained goats as male or female parents for breeding, and select and retain the individuals with relatively more corresponding genotypes in the offspring according to the selection method in claim 8 or 9.

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