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PubMed1998

Least squares interval mapping of quantitative trait loci under the infinitesimal genetic model in outbred populations.

Genetic marker and phenotypic data for a quantitative trait were simulated on 20 paternal half-sib families with 100 progeny to investigate properties of within-family-regression interval mapping of a postulated single quantitative trait locus (QTL) in a marker interval under the infinitesimal genetic model, which has been the basis of the application of quantitative genetics to genetic improvement programs, and to investigate use of the infinitesimal model as null hypothesis in testing for presence of a major QTL. Genetic effects on the marked chromosome were generated based on a major gene model, which simulated a central biallelic QTL, or based on 101 biallelic QTL of equal effect, which approximated the infinitesimal model. The marked chromosome contained 0, 3.3%, 13.3%, or 33.3% of genetic variance and heritability was 0.25 or 0.70. Under the polygenic model with 3.3% of genetic variance on the marked chromosome, which corresponds to the infinitesimal model for the bovine, significant QTL effects were found for individual families. Correlations between estimates of QTL effects and true chromosome substitution effects were 0.29 and 0.47 for heritabilities of 0.25 and 0.70 but up to 0.85 with 33.3% of polygenic variance on the marked chromosome. These results illustrate the potential of marker-assisted selection even under the infinitesimal genetic model. Power of tests for presence of QTL was substantially reduced when the polygenic model with 3.3% of genetic variance on the chromosome was used as a null hypothesis. The ability to determine whether genetic variance on a chromosome was contributed by a single QTL of major effect or a large number of QTL with minor effects, corresponding to the infinitesimal model, was limited.

Chromosome Mapping↗
PubMed2025

Candidate genes at the Rmi1 locus for resistance to Meloidogyne incognita in soybean.

The RKN resistance locus Rmi1 was fine-mapped to two genes on chromosome 10, a glycosyl hydrolase family 9 β-1,4-endoglucanase gene and a type I pectin methylesterase gene. Root-knot nematodes (Meloidogyne spp.) are a serious threat to soybean production in the southeast USA, with yield losses of more than $165 million in 2023. Development and deployment of resistant soybean cultivars is the most effective strategy for managing these nematode pests; however, the identity of the resistance genes and underlying mechanism of resistance remains obscure. An additive resistance gene, Resistance to M. incognita-1 (Rmi1), to the predominant species, was first identified in soybean cultivar Forrest but never mapped to a genomic region. Multiple mapping studies have identified a major quantitative trait locus (QTL) with additive action on chromosome 10. In this study, a population consisting of 170 F2:3 families derived from a cross of Bossier (susceptible) × Forrest (resistant) was initially used to confirm that Rmi1 is in the chromosome 10 QTL. Subsequently, 884 F5:6 recombinant inbred lines (RILs) derived from the same cross were used to fine-map the Rmi1 causal gene(s) to two genes - a β-1,4-endoglucanase (Glyma.10G017000, EG) and a pectin methylesterase/methylesterase inhibitor (Glyma.10G017100, PME1). Both gene candidates have the potential to play a role in the resistance response to M. incognita. Both gene promoters harbor SNPs and indels and the encoded proteins exhibit amino acid polymorphisms, including a premature stop in PME1 of resistant soybeans. Additionally, both genes show a higher expression level in susceptible roots compared to resistant roots in the absence of infection. This suggests that Rmi1 may confer one or more pre-existing differences related to cell wall modification in soybean roots, ultimately leading to a decrease in susceptibility.

Tylenchoidea↗
PubMed2002

[Tagging and mapping of QTLs controlling lint yield and yield components in upland cotton (Gossypium hirsutum L.) using SSR and RAPD markers].

Using interval mapping and marker simple regression methods, the QTLs of yield and its components in (Simian 3 x TM-1) F2 and F2:3, were tagged and Mapped with 39 SSR and 10 RAPD markers having polymorphism between parents screened from 301 pair SSR primers and 1040 RAPD primers. Simian 3 is being grown extensively in Yangtze River cotton-growing valley characterized as high productivity with more bolls and higher lint percent, whereas TM-1, Genetic standard in Upland cotton with more heavy boll weight. In the present report, two QTLs controlling boll size with 18.2% and 21.0% phenotype variance explained in F2:3 generation, one QTL controlling lint percent with 24.9% phenotype variance explained in F2 generation and 5.9% in F2:3 generation and one QTL controlling 100-seed weight with 15.6% phenotype variance explained in F2:3 generation were mapped in Chromosome 9. Additionally, another QTL responsible for 100-seed weight was identified and mapped at the same position in Chromosome 9 in F2:3 generation. It is worth for further to be studied whether it is one QTL for pleiotrophism or two closely linked QTLs. The molecular markers mapped and tagged closely with main QTLs of yield traits in this paper can be used for MAS in cotton high-yield breeding program.

China↗
PubMed2006

Alleles of the bovine DGAT1 variable number of tandem repeat associated with a milk fat QTL at chromosome 14 can stimulate gene expression.

A quantitative trait locus (QTL) affecting milk fat percentage has been mapped to the centromeric end of the bovine chromosome 14 (BTA14). This genomic area includes the DGAT1 gene, which encodes acyl-CoA:diacylglycerol acyltransferase 1, the key enzyme of triglyceride biosynthesis. Genetic and biochemical studies led to the identification of the nonconservative DGAT1-K232A polymorphism as a causal mutation for the QTL. In addition to this, another polymorphism in the 5'-regulatory region of this gene, the DGAT1 variable number of tandem repeat (VNTR), also showed a strong association with milk fat percentage. This promoter VNTR polymorphism affects the number of potential Sp1 binding sites and therefore might have an impact on DGAT1 expression and also milk fat content. Hence, the DGAT1 VNTR polymorphism might be another causal mutation for the BTA14 QTL. However, evidence for Sp1 binding to this polymorphic site and for the capability of DGAT1 VNTR alleles to stimulate gene expression was lacking. In the current work Sp1-VNTR interactions were analyzed by EMSA. In addition, effects of DGAT1 VNTR alleles on gene expression were measured with reporter gene analyses. Conclusions from the results are that 1) the DGAT1 VNTR sequence is indeed a target for Sp1 binding; 2) DGAT1 VNTR alleles can stimulate gene expression in vitro and probably in vivo as well; and 3) although the stimulating effects of the different DGAT1 VNTR alleles did not show significant differences in vitro, their effects on transcription might be different in the chromatin context existing in vivo.

Alleles↗
PubMed2002

Comparative mapping of the wheat 5B short chromosome arm distal region with rice, relative to a crossability locus.

Colinearity between wheat and rice genomes is quite well established at the chromosome level, but less is known at a finer level. We tried to specify these relationships for the wheat 5BS chromosome-arm distal region, where a major locus for crossability was located. By developing AFLP markers, we succeeded to locate this major QTL more precisely. One cloned AFLP fragment mapped to rice chromosome 11, which was in agreement with a rice chromosome-11 linkage block reported in this region. However a second marker, a RFLP probe, showed a break in synteny because it mapped to rice long-arm chromosomes 1 and 5, while screening a rice BAC library with the same probe identified rice chromosomes 5 and 6. Therefore, we concluded that the syntenic relationships were more complex at the fine level. The observed results might indicate the presence of a linkage block carrying a crossability gene on wheat groups 1, 5 and 7, and also on rice chromosomes 5 and 6.

Journal Article↗
PubMed2003

Molecular mapping of capsaicinoid biosynthesis genes and quantitative trait loci analysis for capsaicinoid content in Capsicum.

Quantitative variation in the accumulation of two major capsaicinoids responsible for pungency in the fruit of chile peppers, capsaicin and dihydrocapsaicin, was analyzed in a cross between the non-pungent Capsicum annuum parent cv. Maor and a pungent Capsicum frutescens parent, accession BG 2816. In order to identify quantitative trait loci (QTLs) for capsaicinoid content, we employed the bulked segregant analysis method and screened bulked DNA from F2 individuals at the extremes of the distribution of capsaicinoid content with RAPD primers. Screening with 400 primers allowed the identification of three loci that were polymorphic between the bulks. These RAPD markers were converted to SCARs and subsequently mapped with additional RFLP markers to chromosome 7 of pepper. QTL interval analysis for individual and total capsaicinoid content identified a major QTL, termed cap, which explained 34-38% of the phenotypic variation for this trait in two growing environments. For all measurements, the allele of the pungent parent BG 2816 at cap contributed to the increased level of pungency. To determine whether known structural genes in the pathway could define a candidate for this QTL, 12 clones obtained from differentially expressed transcripts from placental tissue in pungent peppers were also mapped. None of them had a significant effect on this trait, nor did the allelic state at the locus C, the on/off switch for pungency in pepper, located on chromosome 2. The identity of cap and its effect on capsaicin content in other backgrounds will be addressed in future studies.

Alleles↗
PubMed2002

Comparative analysis of QTLs affecting plant height and flowering among closely-related diploid and polyploid genomes.

Quantitative trait loci (QTLs) affecting plant height and flowering were studied in the two Saccharum species from which modern sugarcane cultivars are derived. Two segregating populations derived from interspecific crosses between Saccharum officinarum and Saccharum spontaneum were genotyped with 735 DNA markers. Among the 65 significant associations found between these two traits and DNA markers, 35 of the loci were linked to sugarcane genetic maps and 30 were unlinked DNA markers. Twenty-one of the 35 mapped QTLs were clustered in eight genomic regions of six sugarcane homologous groups. Some of these could be divergent alleles at homologous loci, making the actual number of genes implicated in these traits much less than 35. Four QTL clusters controlling plant height in sugarcane corresponded closely to four of the six plant-height QTLs previously mapped in sorghum. One QTL controlling flowering in sugarcane corresponded to one of three flowering QTLs mapped in sorghum. The correspondence in locations of QTLs affecting plant height and flowering in sugarcane and sorghum reinforce the notion that the simple sorghum genome is a valuable "template" for molecular dissection of the much more complex sugarcane genome.

Chromosome Mapping↗
PubMed2004

Mapping tissue-specific genes correlated with age-dependent changes in protein stability and function.

Biophysical measurements indicative of protein stability and function were performed on crude extracts from liver, muscle, and lens of a genetically heterogeneous mouse population. Genetic information was used to search for quantitative trait loci (QTL) that influenced the biophysical traits, with emphasis on phenotypes that previously have been shown to be altered in aged animals. Spectroscopic and enzymatic assays of crude liver and muscle tissue extracts from approximately 600 18-month-old mice, the progeny of (BALB/cJxC57BL/6J)F1 females and (C3H/HeJxDBA/2J)F1 males, were used to measure the susceptibility of a ubiquitous glycolytic enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), to thermal denaturation. The rate constant for thermal inactivation of GAPDH correlated with markers on chromosome 5 (D5Mit79 and D5Mit251) for muscle lysates and chromosome 15 (D15Mit63 and D15Mit100) for liver tissue. The degree of variability of inactivation rate constants, a measure of the heterogeneity of muscle GAPDH in tissue extracts, was also associated with markers on chromosome 5 (D5Mit79 and D5Mit205). In addition, spectroscopic characteristics of extracted eye lens proteins were evaluated for their susceptibility to photooxidative stress. Absorbance and fluorescence emission characteristics of the lens proteins were mapped to QTL on chromosomes 5 and 15 (D5Mit25 and D15Mit171) while the degree of heterogeneity in photochemical oxidation kinetics was associated with a marker on the chromosome 8 (D8Mit42). Recent work has shown that GAPDH possesses a number of non-glycolytic functions including DNA/RNA binding and regulation of protein expression. Tissue specific differences in GAPDH stability may have significant consequences to these alternate functions during aging.

Aging↗
PubMed2003

Conservation of the syntenies between porcine chromosome 7 and human chromosomes 6, 14 and 15 demonstrated by radiation hybrid mapping and linkage analysis.

Comparative mapping studies facilitate the identification of genes located in quantitative trait locus (QTL) regions in domestic animals by utilizing information from the human genome. Radiation hybrid (RH) mapping is effective for this purpose because of its high resolution in ordered gene mapping on chromosomes. We constructed an RH map of pig chromosome 7, by adding 23 markers associated with genes. This RH map clearly demonstrated the mosaic of homology between pig chromosome 7 (SSC7) and human chromosomes 6, 14 and 15 at a 'gene' level, and was confirmed by linkage analysis. Clarification of the homology of SSC7 to human chromosomes will contribute to the elucidation of the gene(s) responsible for QTL detected on this chromosome.

Animals↗
PubMed2005

Molecular characterization and mapping of ALMT1, the aluminium-tolerance gene of bread wheat (Triticum aestivum L.).

The major aluminum (Al) tolerance gene in wheat ALMT1 confers. An Al-activated efflux of malate from root apices. We determined the genomic structure of the ALMT1 gene and found it consists of 6 exons interrupted by 5 introns. Sequencing a range of wheat genotypes identified 3 alleles for ALMT1, 1 of which was identical to the ALMT1 gene from an Aegilops tauschii accession. The ALMT1 gene was mapped to chromosome 4DL using 'Chinese Spring' deletion lines, and loss of ALMT1 coincided with the loss of both Al tolerance and Al-activated malate efflux. Aluminium tolerance in each of 5 different doubled-haploid populations was found to be conditioned by a single major gene. When ALMT1 was polymorphic between the parental lines, QTL and linkage analyses indicated that ALMT1 mapped to chromosome 4DL and cosegregated with Al tolerance. In 2 populations examined, Al tolerance also segregated with a greater capacity for Al-activated malate efflux. Aluminium tolerance was not associated with a particular coding allele for ALMT1, but was significantly correlated with the relative level of ALMT1 expression. These findings suggest that the Al tolerance in a diverse range of wheat genotypes is primarily conditioned by ALMT1.

Alleles↗
PubMed2006

Amh and Dmrta2 genes map to tilapia (Oreochromis spp.) linkage group 23 within quantitative trait locus regions for sex determination.

Recent studies have revealed that the major genes of the mammalian sex determination pathway are also involved in sex determination of fish. Several studies have reported QTL in various species and strains of tilapia, regions contributing to sex determination have been identified on linkage groups 1, 3, and 23. Genes contributing to sex-specific mortality have been detected on linkage groups 2, 6, and 23. To test whether the same genes might control sex determination in mammals and fishes, we mapped 11 genes that are considered putative master key regulators of sex determination: Amh, Cyp19, Dax1, Dmrt2, Dmrta2, Fhl3l, Foxl2, Ixl, Lhx9, Sf1, and Sox8. We identified polymorphisms in noncoding regions of these genes and genotyped these sites for 90 individuals of an F2 mapping family. Mapping of Dax1 joined LG16 and LG21 into a single linkage group. The Amh and Dmrta2 genes were mapped to two distinct regions of LG23. The Amh gene was mapped 5 cM from UNH879 within a QTL region for sex determination and 2 cM from UNH216 within a QTL region for sex-specific mortality. Dmrta2 was mapped 4 cM from UNH848 within another QTL region for sex determination. Cyp19 was mapped to LG1 far from a previously reported QTL region for sex determination on this chromosome. Seven other candidate genes mapped to LG4, -11, -12, -14, and -17.

Animals↗
PubMed2005

Mapping regulatory genes as candidates for cold and drought stress tolerance in barley.

Cereal crop yield is greatly affected in many growing areas by abiotic stresses, mainly low temperature and drought. In order to find candidates for the tolerance genes for these stresses, 13 genes encoding for transcription factors and upstream regulators were screened by amplification and SSCP on six parental genotypes of three barley mapping populations ('Nure' x 'Tremois', 'Proctor' x 'Nudinka', and 'Steptoe' x 'Morex'), and mapped as newly developed STS, SNP, and SSCP markers. A new consensus function map was then drawn using the three maps above, including 16 regulatory candidate genes (CGs). The positions of barley cold and drought tolerance quantitative trait loci (QTLs) presently described in the literature were added to the consensus map to find positional candidates from among the mapped genes. A cluster of six HvCBF genes co-mapped with the Fr-H2 cold tolerance QTL, while no QTLs for the same trait were positioned on chromosome 7H, where two putative barley regulators of CBF expression, ICE1 and FRY1, found by homology search, were mapped in this work. These observations suggest that CBF gene(s) themselves, rather than their two regulators, are at present the best candidates for cold tolerance. Four out of 12 drought tolerance QTLs of the consensus map are associated with regulatory CGs, on chromosomes 2H, 5H, and 7H, and two QTLs with effector genes, on chromosomes 5H and 6H. The results obtained could be used to guide MAS applications, allowing introduction into an ideal genotype of favourable alleles of tolerance QTLs.

Chromosome Mapping↗
PubMed2004

Tagging quantitative trait loci for maturity-corrected late blight resistance in tetraploid potato with PCR-based candidate gene markers.

Late blight caused by the oomycete Phytophthora infestans is the economically most important and destructive disease in potato cultivation. Quantitative resistance to late blight available in tetraploid cultivars is correlated with late maturity in temperate climates, which is an undesirable characteristic. A total of 30 DNA-based markers known to be linked to loci for pathogen resistance in diploid potato were selected and tested as polymerase chain reaction-based markers for linkage with quantitative trait loci (QTL) for late blight resistance and plant maturity in two half-sib families of tetraploid potatoes. Most markers originated from within or were physically closely linked to candidate genes for quantitative resistance factors. The families were repeatedly evaluated in the field for quantitative resistance to late blight and maturity. Resistance was corrected for the maturity effect. Nine of eleven different map segments tagged by the markers harbored QTL affecting maturity-corrected resistance. Interactions were found between unlinked resistance QTL, providing testable strategies for marker-assisted selection in tetraploid potato. Based on the linkage observed between QTL for resistance and plant maturity and based on the genetic interactions observed between candidate genes tagging resistance QTL, we discuss models for the molecular basis of quantitative resistance and maturity.

Alleles↗
PubMed2001

Evidence for new alleles in the protein kinase adenosine monophosphate-activated gamma(3)-subunit gene associated with low glycogen content in pig skeletal muscle and improved meat quality.

Several quantitative trait loci (QTL) affecting muscle glycogen content and related traits were mapped to pig chromosome 15 using a three-generation intercross between Berkshire x Yorkshire pigs. On the basis of the QTL location the PRKAG3 (protein kinase, AMP-activated, gamma(3)-subunit) gene was considered to be a good candidate for the observed effects. Differences in the PRKAG3 gene sequences of the founder animals of the intercross were analyzed. The RN(-) mutation previously reported was not present in the cross but three missense substitutions and a polymorphic short interspersed element (SINE) were identified. To confirm the hypothesis that at least one of these mutations was associated with differences in meat quality, >1800 animals from several unrelated commercial lines were genotyped for the candidate substitutions and an association study was performed. The results demonstrate the presence of new economically important alleles of the PRKAG3 gene affecting the glycogen content in the muscle and the resulting meat quality. Haplotype analysis was shown to resolve the effects of PRKAG3 more clearly than analysis of individual polymorphisms. Because of their prevalence in the more common commercial breeds, the potential implications for the pig industry and consumers are considerably greater than the original discovery of the RN(-) mutation. Furthermore, these results illustrate that additional alleles of genes involved in major mutations may play a significant role in quantitative trait variation.

Alleles↗
PubMed2005

Extensive chromosomal repatterning and the evolution of sterility barriers in hybrid sunflower species.

New species may arise via hybridization and without a change in ploidy. This process, termed homoploid hybrid speciation, is theoretically difficult because it requires the development of reproductive barriers in sympatry or parapatry. Theory suggests that isolation may arise through rapid karyotypic evolution and/or ecological divergence of hybrid neospecies. Here, we investigate the role of karyotypic change in homoploid hybrid speciation by generating detailed genetic linkage maps for three hybrid sunflower species, Helianthus anomalus, H. deserticola, and H. paradoxus, and comparing these maps to those previously generated for the parental species, H. annuus and H. petiolaris. We also conduct a quantitative trait locus (QTL) analysis of pollen fertility in a BC2 population between the parental species and assess levels of pollen and seed fertility in all cross-combinations of the hybrid and parental species. The three hybrid species are massively divergent from their parental species in karyotype; gene order differences were observed for between 9 and 11 linkage groups (of 17 total), depending on the comparison. About one-third of the karyoypic differences arose through the sorting of chromosomal rearrangements that differentiate the parental species, but the remainder appear to have arisen de novo (six breakages/six fusions in H. anomalus, four breakages/three fusions in H. deserticola, and five breakages/five fusions in H. paradoxus). QTL analyses indicate that the karyotypic differences contribute to reproductive isolation. Nine of 11 pollen viability QTL occur on rearranged chromosomes and all but one map close to a rearrangement breakpoint. Finally, pollen and seed fertility estimates for F1's between the hybrid and parental species fall below 11%, which is sufficient for evolutionary independence of the hybrid neospecies.

Chromosome Mapping↗
PubMedDate not supplied

Linkage mapping of the ovine alpha-inhibin (INHA) beta(A)-inhibin/activin (INHBA) and beta(B)-inhibin/activin (INHBB) genes.

A full-sib mapping population was typed for Taql Southern blot RFLPs at the ovine alpha-inhibin (INHA), beta(A)-inhibin/activin (INHBA), and beta(B)-inhibin/activin (INHBB) loci. The most likely positions were found by genetic linkage analysis. INHA was placed on ovine chromosome 2q, between microsatellite markers BM6444 and INRA135, while INHBB was located 39 cM proximal to INHA between markers BMS1126 and BMS2626. The INHBA gene, a comparative mapping anchor locus, mapped to chromosome 4, between microsatellites OARCP26 and BMS719. These data confirm and refine previous chromosomal assignments by in situ hybridization, provide comparative mapping information, and identify microsatellite markers suitable for QTL association studies with inhibin/activin genes in ruminants.

Activins↗
PubMed2006

A type I and type II microsatellite linkage map of rainbow trout (Oncorhynchus mykiss) with presumptive coverage of all chromosome arms.

BACKGROUND: The development of large genomic resources has become a prerequisite to elucidate the wide-scale evolution of genomes and the molecular basis of complex traits. Linkage maps represent a first level of integration and utilization of such resources and the primary framework for molecular analyses of quantitative traits. Previously published linkage maps have already outlined the main peculiarities of the rainbow trout meiosis and a correspondance between linkage groups and chromosome arms has been recently established using fluorescent in situ hybridization. The number of chromosome arms which were covered by these maps remained unknown. RESULTS: We report an updated linkage map based on segregation analysis of more than nine hundred microsatellite markers in two doubled haploid gynogenetic lines. These markers segregated into 31 linkage groups spanning an approximate total map length of 2750 cM. Centromeres were mapped for all the linkage groups using meiogenetic lines. For each of the 31 linkage groups, the meta or acrocentric structure infered from centromere mapping was identical with those recently found with fluorescent in situ hybridization results. The present map is therefore assumed to cover the 52 chromosome arms which constitute the rainbow trout karyotype. Our data confirm the occurrence of a high interference level in this species. Homeologous regions were identified in eleven linkage groups, reflecting the tetraploid nature of the salmonid genome. The data supported the assumption that gene orders are conserved between duplicated groups and that each group is located on a single chromosome arm. Overall, a high congruence with already published rainbow trout linkage maps was found for both gene syntenies and orders. CONCLUSION: This new map is likely to cover the whole set of chromosome arms and should provide a useful framework to integrate existing or forthcoming rainbow trout linkage maps and other genomic resources. Since very large numbers of EST containing microsatellite sequences are available in databases, it becomes feasible to construct high-density linkage maps localizing known genes. This will facilitate comparative mapping and, eventually, identification of candidate genes in QTL studies.

Animals↗
PubMed2001

Linkage map construction in the outcrossing species Lolium perenne.

Genetic maps have proven useful tools in several fields of application. First of all, they allow to get insight into the genome organization of a species, and to compare the genome structures of different species. Genetic maps are also useful for the identification of genomic regions involved in physiological processes, and are valuable tools for the positional cloning of genes. In the framework of a project with the aim of identifying genomic regions involved in disease resistance in Lolium spp., we constructed genetic maps using different marker systems. In the ryegrass species L. perenne and L. multiflorum self-pollination is prevented by a very efficient self incompatibility system. This has clear implications in mapping studies: inbred lines and double haploids are difficult to produce, and if produced low seed yields are obtained. For this reason, we created several mapping populations by crossing two highly heterozygous unrelated plants. This implies that at any given locus, up to four different alleles might be segregating in the offspring. Different marker systems were used for the construction of the genetic maps. In first instance, AFLP was used as a high throughput marker system. This allowed to generate a high number of DNA-markers useful for map construction in a quick way. The drawback of the AFLP technique is twofold: AFLP markers are 'anonymous', and are dominant (not all alleles at a locus can be detected). Co-dominant marker systems, which allow to detect all alleles present at any locus, are much more informative and are required for the construction of detailed linkage maps in outcrossers. In this study, we used three co-dominant marker systems: SSR, STS and RFLP. The RFLP markers were generated using heterologous probes derived from other monocots, what should allow to analyze the syntenic relationships between ryegrass and other monocots. Using these markers generated with different techniques, a genetic map of ryegrass has been constructed suitable for QTL analysis and comparative genetics.

Chromosome Mapping↗