48 results about "Qtl analysis" patented technology

A method for associating a gene G in the genome of a species with a clinical trait T exhibited by one or more organisms in a plurality of organisms of the species. An expression quantitative trait loci (eQTL) is identified for the gene G using a first quantitative trait loci (QTL) analysis. The first QTL analysis uses a plurality of expression statistics for gene G as a quantitative trait. Each expression statistic in the plurality of expression statistics represents an expression value for gene G in an organism in the plurality of organisms. A clinical quantitative trait loci (cQTL) that is linked to the clinical trait T is identified using a second QTL analysis. The second QTL analysis uses a plurality of phenotypic values as a quantitative trait. Each phenotypic value in the plurality of phenotypic values represents a phenotypic value for the clinical trait T in an organism in the plurality of organisms. When the eQTL and the cQTL colocalize to the same locus, the gene G is associated with clinical trait T.

Provided herein are methods for evaluating associations between candidate genes and a trait of interest in a population. The methods include a combination of genome-wide association analysis and one or more of nested association mapping (NAM), expression QTL analysis (eQTL), and allele epistastic analysis (AEA). Markers are selected or prioritized if they are shown to be positively-correlated with a trait of interest using GWA and a combination of one or both of NAM and eQTL. Also provided are models for evaluating the association between a candidate marker and a trait in a nested population of organisms. These methods include single marker regression and multiple marker regression models. Markers identified using the methods of the invention can be used in marker assisted breeding and selection, as genetic markers for constructing linkage maps, for gene discovery, for identifying genes contributing to a trait of interest, and for generating transgenic organisms having a desired trait.

The invention relates to a chrysanthemum-branching-trait-related molecular marker acquisition method, and belongs to the technical field of biology. The method comprises the steps that: a, a testing material and phenotypic data thereof are obtained; b, a chrysanthemum linkage map is established; c, chrysanthemum branching trait QTL analysis is carried out according to the phenotypic data and a molecular genetic map; and d, chrysanthemum-branching-trait-related molecular markers are determined. According to the invention, 'QX-145' (P1) is adopted as a female parent, NanNongYinShan is adopted as a male parent (P2), and 92 F1 segregating populations obtained by hybridization are adopted as the testing material; and a plurality of molecular markers substantially related to chrysanthemum branching traits are obtained. The molecular markers can be used in chrysanthemum branching trait good gene fine positioning and cloning, such that selection efficiency can be greatly improved, and breeding process can be accelerated.

The invention provides a maize single panicle weight main effect QTL, as well as an acquisition method and application thereof. The QTL comprises qEW-1, qEW-2, qEW-3, qEW-4 and qEW-5. The method comprises the following steps: configuring cross combination by taking a high-yield early-maturity maize inbred line SG5 as a female parent and a maize inbred line SG7 with relatively poor yield trait as a male parent, and constructing an F2 genetic group of the cross combination; performing GBS sequencing-basing typing on the F2 genetic group, and performing genotyping by combining differential SNP validated based on SG5 and SG7 parents; investigating the yield trait of single F2 panicle, performing QTL analysis on the F2 single panicle yield trait by utilizing a winQTLcart2.5 software composite interval mapping method, and analyzing the chromosome region of the main effect QTL and the genetic effect. According to the method, a theoretic base is provided to excavating and controlling the maize single panicle weight main effect QTL and linked marker, a molecular marker closely linked with the target QTL is acquired, and foundation is laid to maize single panicle yield trait QTL candidate gene prediction, cloning and molecular mark assisted breeding.

The invention relates to a molecular marker of paddy-rice stalk-strengthening lodging-resistant gene prl4 and application of the molecular marker. QTL (quantitative trait loci) analysis is performed on F2 and RILs crowds of lodging-resistant correlated character of japonica type super rice Shennong 265 and Yunnan local japonica rice variety Lijiangxintuanheigu, so that major QTL is identified, which is stably expressed in different crowd type (F2 and RILs), at different years (2008, 2009 and 2011) at different place (Shenyang and Haerbin), and a synergistic allelomorphic gene of major QTL comes from Yunnan local japonica rice variety Lijiangxintuanheigu. Further analysis shows that the major QTL simultaneously controls push-resistant strength of the lower part of a plant, breaking-resistant strength of a stem, stem wall thickness, area of larger vascular bundle and smaller vascular bundle, and xylem area of larger vascular bundle and smaller vascular bundle. The major QTL is named as prl4 (pushing resistance of the lower part 4). The invention also discloses a molecular marker of prl4. The molecular marker is closely linked with prl4, and is separated with prl4 in a plant later generation, so that a molecular-marker assistant means is applicable to selectively culture paddy rice varieties possessing both high-yield property and lodging resistance.

The invention belongs to the field of grape molecular breeding, and particularly provides a molecular marker for a grape fruit seedless major QTL site and an application. An RAD-seq method is utilizedfor sequencing and constructing a joint genetic linkage map of a female parent 'Red Globe' and a male parent 'Centenial Seedless', identification is carried out in combination with a grape fruit phenotype, and an interval mapping method is utilized for QTL analysis, then the presence of the major QTL site (i)SDL(/i) is detected in combination with a 18th linkage group in the genetic linkage map,a contribution rate of the major QTL site is 77.9%, and two SNP markers closely linked to the site are SDL1 and SDL2, with a genetic distance of 124kb. The SNP molecular marker for the grape fruit seedless major QTL site obtained in the invention can be used for early screening of grape fruit seedless traits, and has important theoretical and practical guiding significance for improving the breeding efficiency.

The invention belongs to the field of pear molecule breeding, and provides a molecular marker of a pear fruit single fruit weight main-effect QTL (quantitative trait loci) site, and application thereof. A starkrimson and Wanxiu pear combined genetic linkage map is built by SSR (simple sequence repeat) marker; the pear fruit single fruit weight phenotype identification is combined; in addition, an interval mapping method is used for QTL analysis; the existence of the main-effect QTL site is detected at the eleventh linkage group of the combined linkage map; the contribution rate of the main-effect QTL site is 51.9 percent. The SSR marker tightly linked with the main-effect QTL site is QS1122-135, and the genetic distance is 4.37cm. The obtained pear fruit single fruit weight main-effect QTL molecular marker can be used for early selection on the basis of fruit characters of single fruit weight; the important theoretical and practice guidance significance is realized for improving the breeding efficiency.

Through creation of a detailed linkage map of barley and QTL analysis thereof, there have been found five genetic markers linked to gene locus involved in barley resistance to yellow mosaic disease and situated on barley 1H chromosome, two genetic markers linked to gene locus involved in barley resistance to yellow mosaic disease and situated on barley 2H chromosome barley resistance to yellow mosaic disease, five genetic markers linked to gene locus involved in barley resistance to yellow mosaic disease and situated on barley 3H chromosome, four genetic markers linked to gene locus involved in barley resistance to yellow mosaic disease and situated on barley 4H chromosome, and two genetic markers linked to gene locus involved in barley resistance to yellow mosaic disease and situated on barley 5H chromosome.

By a QTL analysis and so forth using 4-HPPD inhibitor-susceptible rice and 4-HPPD inhibitor-resistant rice, a hypothetical gene (HIS1 gene) of an iron/ascorbate-dependent oxidoreductase gene located on a short arm of chromosome 2 of rice has been identified as a 4-HPPD inhibitor-resistance gene. Further, it has also been revealed that a homologous gene (HSL1 gene) of the HIS1 gene is located on chromosome 6 of rice. Furthermore, it has been found out that utilizations of these genes make it possible to efficiently produce a plant having increased resistance or susceptibility to a 4-HPPD inhibitor and to efficiently determine whether a plant has resistance or susceptibility to a 4-HPPD inhibitor.

The invention relates to the technical field of molecular markers, especially to a primer group of a taro and application thereof. According to the invention, the taro is used as a material, and the DNA of the taro is extracted and subjected to enzyme digestion, sequencing and analysis to obtain corresponding SSR primers, so more effective SSR markers can be provided for application research of genetic diversity and genetic relationship of the taro; analysis shows that the primers have the characteristic of high polymorphic percentage, and amplification effect is better when the primers are used for verification; selection of the primer group provides a valuable genetic tool for research, such as QTL analysis, genetic relationship identification, genetic diversity research and heterosis prediction, of the taro in genetic breeding, and a reference basis can be provided for reasonable selection and matching of breeding parents of the taro and innovative utilization of taro germplasm through research on the genetic relationship between pedigree parents.

The invention discloses a gene mapping multi-inspection method. The method is characterized by comprising the steps of 1, sequencing a parent DNA sample and a filial generation DNA sample to obtain a high-precision short segment sequence; 2,comparing the obtained high-precision short segment sequence with a reference sequence, or mutually clustering to obtain accurate SNP information; 3, converting the SNP information into group SNP, further converting into a standard molecular standard format, creating a genetic map, and performing QTL analysis on the basis of the genetic map to obtain QTL seat information; 4, identifying the phenotype information of filial generation DNA sample, accurately counting the phenotype value distribution, grouping the phenotype values according to gradient, respectively blending the high-precision short segment sequences of the filial generation DNA sample, corresponding to the extreme phenotype values, analyzing the genotype frequency distribution, and performing chi-square test and rank sum test to find out related obvious areas; 5, integrating the QTL seat information and the accurate gene mapping information obtained in step 4.

The invention discloses a molecular marker for regulating main effect QTL (quantitative trait loci) of hundred-grain weight of corn and application of the molecular marker. By taking general DNA of corn as a template, PCR amplification is carried out on SSR primers Sym035 and Sym119 to obtain DNA fragments which are 165 bp and 147 bp long through gel electrophoresis; a QTL for regulating hundred-grain weight of corn exists between the SSR molecular markers Sym035 and Sym119 on a Bin5.06 region on the fifth chromosome. By using similar F2: 3 colony, QTL analysis on grain length, grain width and grain thickness show that a QTL for grain width is positioned between the molecular markers Sym024 and Sym128, and the genetic distance is 13.1cM. Correlation coefficients between hundred-grain weight and grain length, grain width and grain thickness in a segregation population are respectively 0.532, 0.726 and 0.187. Reduction of hundred-grain weight of single segment substitution lines SSSL-Z22 is mainly induced by reduction of grain width.

It is to provide a novel molybdenum ion transporter MoTR1 gene responsible for molybdenum transport for the first time in plants, enabling to promote effectively molybdenum absorption from the environment or molybdenum transport in vivo. By QTL analysis of Arabidopsis thaliana accessions Col-0 and Ler, it was found that QTL which dominates Mo concentration in leaves was present on the chromosome No: 2. In the present invention, the region in which the causal gene is present was limited to 172 kb, by a genetic analysis. In the region, the gene At2g25680 having a domain common to sulfate ion transporter, while its function is not revealed was present. Thus, knockout strains of 2 separate lines in which a foreign gene fragment (T-DNA) was introduced at At2g25680 were obtained, Mo concentration in leaves was measured, and MoTR1 gene was identified.

The invention discloses a QTL (Quantitative Trait Locus) linked molecular marker for controlling corn female parent haploidy production. The molecular marker comprises a primer umc1295, wherein the sequence of the primer umc1295 is SEQ ID NO: F1:5'-GTCGATCTTCCTCCCCATCA-3'; SEQ ID NO: R1: 5'-CGTTTCTATCTATGGAGGAGTGCG-3'. Through SSR molecular marker and QTL analysis, a QTL locus for controlling the corn female parent haploidy production exists on a seventh chromosome, is linked with the molecular marker umc1295, and is located on 7.04bin of the seventh chromosome. The analysis result indicates that whether the marker exists or not directly relates to the haploidy production capacity of plants, and the marker can be used for forecasting female parent haploidy production frequency. Compared with the prior art, through the detection of the molecular marker, the haploidy production capacity of corn female parent can be forecasted in an early stage, so that the blindness of induction is reduced, the induction efficiency is improved, and the engineering application of a haploidy breeding technique is accelerated.

QTL analysis on the resistance to Fusarium head blight is performed by using an RI line (RHI population) grown by crossing Russia 6 (two-row, resistant) with H.E.S.4 (six-row, susceptible), an RI line (RI2 population) grown by crossing Harbin 2-row (resistant) with Turkey 6 (susceptible), and a DH line (DHHS population) grown by crossing Haruna Nijo (resistance) with H602 (susceptible). As a result, QTLs are detected on the 2H, 4H and 5H chromosomes in the RHI population, on the 2H, 4H and 6H chromosomes in the RI2 population and on the 2H, 4H and 5H chromosomes in the DHHS population. Furthermore, genetic markers linked to these QTLs (MM314, FM677, FM426, MM1057, MMtgaEatc128, FMgcgEatc 530, FXLRRfor_XLRRrev119, FMacgEcgt288, HVM67, FMataEagc408, HVM11, Bmag125, k04002, k05042, k03289, HvLOX and k00835) are found out.

The invention discloses a strong-winter winter rape (Brassica campestris) SOD enzyme molecular marker and a QTL locus. A screening process includes following steps: (1) performing hybridization between a multi-generation bagged-selfing parent strong-winter super-cold-winder-resistant rape 'Longyou #7' and strong-cold-winder-resistant rape 'Longyou #9' to construct an F2-generation segregation population; (2) extracting leaf DNA of the two parents and the F2-generation segregation population through the CTAB method; (3) performing polymorphic primer screening to the two parent DNA through SSR and InDel primers; (4) obtaining genotype data through the F2-generation segregation population to construct a genetic linkage map and carry out QTL analysis; and (5) obtaining two QTL loca of SOD enzyme of the strong-winter winter rape (Brassica campestris), which are respectively named Qsod.gsau-6A and Qsod.gsau-7A. Four molecular markers, which are linked with the QTL loca of the SOD enzyme of the strong-winter winter rape (Brassica campestris), are respectively named Ra1-F06, Ra2-D04, 8C0108 and Ol12E03.

The invention discloses a group of QTL (quantitative trait locus) sites controlling relevant characters of epidermal hair and stomata of wheat and an analysis method and belongs to the field of molecular biology. The QTL sites comprise Qtd-2A-1, Qtd-2B-1, Qtd-7D-1, Qtl-7D-1, Qtl-7D-2, Qsl-6A-1, Qsl-5A-2 and Qsl-4A. The QTL analysis method comprises the steps of: (1) constructing a wheat DH population, (2) collecting phenotype data of the relevant characters of the epidermal hair and the stomata of the wheat under normal irrigation and drought stress conditions, and (3) performing QTL analysisusing a genetic linkage map according to the phenotype data. The QTL sites and the analysis method have the benefits that the influence of the drought stress condition on the relevant characters of the epidermal hair and the stomata is researched; at the same time, QTL analysis is performed on the relevant characters of the epidermal hair and the stomata in different positions of leaves under thetwo moisture conditions; and the stable expression QTL sites in different environments are explored.

The invention discloses strong winterness brassia campestris L. soluble protein content molecule markers and QTL loci. The screening steps are that (1), multi-generation bagging selfing parent strong winterness superstrong cold resistant winter rape 'the 7th Longyou' and strong cold resistant winter rape 'the 9th Longyou' are utilized for hybridization to construct a generation F2 segregation population; (2), a CTAB method is utilized for extracting leaf DNA of the generation F2 segregation population and the two parents; (3), SSR and InDel primers are utilized for performing polymorphism primer selection on the DNA of the two parents; (4), genetype data are obtained through the generation F2 segretation population to construct a genetic linkage map and QTL analysis; and (5), two strong winterness brassia campestris L. soluble protein content QTL loci are obtained and named as Qsol.gsau-8A; and two molecule markers linked with the strong winterness brassia campestris L. soluble protein content QTL loci are BrID10839 and Ra2-E12.