The Genetic Map Comparator: a user-friendly application to display and compare genetic maps

AbstractGenetic map is a linear arrangement of the relative positions of sites in the chromosome or genome based on the recombination frequency between genetic markers. It is the important basis for genetic analysis. Several kinds of software have been designed for genetic mapping, but all these tools require users to write or edit code, making it time-costing and difficult for researchers without programming skills to handle with. Here, MG2C, a new online tool was designed, based on PERL and SVG languages.Users can get a standard genetic map, only by providing the location of genes (or quantitative trait loci) and the length of the chromosome, without writing additional code. The operation interface of MG2C contains three sections: data input, data output and parameters. There are 33 attribute parameters in MG2C, which are further divided into 8 modules. Values of the parameters can be changed according to the users’ requirements. The information submitted by users will be transformed into the genetic map in SVG file, which can be further modified by other image processing tools.MG2C is a user-friendly and time-saving online tool for drawing genetic maps, especially for those without programming skills. The tool has been running smoothly since 2015, and updated to version 2.1. It significantly lowers the technical barriers for the users, and provides great convenience for the researchers.

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Heterogeneity in Rates of Recombination Across the Mouse Genome

Genetics ◽

10.1093/genetics/142.2.537 ◽

1996 ◽

Vol 142 (2) ◽

pp. 537-548 ◽

Cited By ~ 2

Author(s):

Michael W Nachman ◽

Gary A Churchill

Keyword(s):

Linkage Map ◽

Genetic Map ◽

Large Scale ◽

Physical Map ◽

Genetic Maps ◽

Recombination Rates ◽

Physical Maps ◽

Genomic Patterns ◽

Mary Lyon ◽

Microsatellite Linkage

Abstract If loci are randomly distributed on a physical map, the density of markers on a genetic map will be inversely proportional to recombination rate. First proposed by MARY LYON, we have used this idea to estimate recombination rates from the Drosophila melanogaster linkage map. These results were compared with results of two other studies that estimated regional recombination rates in D. melanogaster using both physical and genetic maps. The three methods were largely concordant in identifying large-scale genomic patterns of recombination. The marker density method was then applied to the Mus musculus microsatellite linkage map. The distribution of microsatellites provided evidence for heterogeneity in recombination rates. Centromeric regions for several mouse chromosomes had significantly greater numbers of markers than expected, suggesting that recombination rates were lower in these regions. In contrast, most telomeric regions contained significantly fewer markers than expected. This indicates that recombination rates are elevated at the telomeres of many mouse chromosomes and is consistent with a comparison of the genetic and cytogenetic maps in these regions. The density of markers on a genetic map may provide a generally useful way to estimate regional recombination rates in species for which genetic, but not physical, maps are available.

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An enhanced molecular marker based genetic map of perennial ryegrass (Lolium perenne) reveals comparative relationships with other Poaceae genomes

Genome ◽

10.1139/g01-144 ◽

2002 ◽

Vol 45 (2) ◽

pp. 282-295 ◽

Cited By ~ 175

Author(s):

Elizabeth S Jones ◽

Natalia L Mahoney ◽

Michael D Hayward ◽

Ian P Armstead ◽

J Gilbert Jones ◽

...

Keyword(s):

Molecular Marker ◽

Linkage Map ◽

Genetic Map ◽

Lolium Perenne ◽

Perennial Ryegrass ◽

Genetic Linkage Map ◽

Population Based ◽

Genetic Maps ◽

Linkage Groups ◽

Integrated Genetic Map

A molecular-marker linkage map has been constructed for perennial ryegrass (Lolium perenne L.) using a one-way pseudo-testcross population based on the mating of a multiple heterozygous individual with a doubled haploid genotype. RFLP, AFLP, isoenzyme, and EST data from four collaborating laboratories within the International Lolium Genome Initiative were combined to produce an integrated genetic map containing 240 loci covering 811 cM on seven linkage groups. The map contained 124 codominant markers, of which 109 were heterologous anchor RFLP probes from wheat, barley, oat, and rice, allowing comparative relationships between perennial ryegrass and other Poaceae species to be inferred. The genetic maps of perennial ryegrass and the Triticeae cereals are highly conserved in terms of synteny and colinearity. This observation was supported by the general agreement of the syntenic relationships between perennial ryegrass, oat, and rice and those between the Triticeae and these species. A lower level of synteny and colinearity was observed between perennial ryegrass and oat compared with the Triticeae, despite the closer taxonomic affinity between these species. It is proposed that the linkage groups of perennial ryegrass be numbered in accordance with these syntenic relationships, to correspond to the homoeologous groups of the Triticeae cereals.Key words: Lolium perenne, genetic linkage map, RFLP, AFLP, conserved synteny.

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AFLAP: Assembly-Free Linkage Analysis Pipeline using k-mers from whole genome sequencing data

10.1101/2020.09.14.296525 ◽

2020 ◽

Author(s):

Kyle Fletcher ◽

Lin Zhang ◽

Juliana Gil ◽

Rongkui Han ◽

Keri Cavanaugh ◽

...

Keyword(s):

Linkage Analysis ◽

Whole Genome Sequencing ◽

Genome Sequencing ◽

Genetic Map ◽

Genotyping By Sequencing ◽

Genetic Maps ◽

Whole Genome ◽

Sequencing Data ◽

Analysis Pipeline ◽

Genome Assemblies

AbstractBackgroundGenetic maps are an important resource for validation of genome assemblies, trait discovery, and breeding. Next generation sequencing has enabled production of high-density genetic maps constructed with 10,000s of markers. Most current approaches require a genome assembly to identify markers. Our Assembly Free Linkage Analysis Pipeline (AFLAP) removes this requirement by using uniquely segregating k-mers as markers to rapidly construct a genotype table and perform subsequent linkage analysis. This avoids potential biases including preferential read alignment and variant calling.ResultsThe performance of AFLAP was determined in simulations and contrasted to a conventional workflow. We tested AFLAP using 100 F2 individuals of Arabidopsis thaliana, sequenced to low coverage. Genetic maps generated using k-mers contained over 130,000 markers that were concordant with the genomic assembly. The utility of AFLAP was then demonstrated by generating an accurate genetic map using genotyping-by-sequencing data of 235 recombinant inbred lines of Lactuca spp. AFLAP was then applied to 83 F1 individuals of the oomycete Bremia lactucae, sequenced to >5x coverage. The genetic map contained over 90,000 markers ordered in 19 large linkage groups. This genetic map was used to fragment, order, orient, and scaffold the genome, resulting in a much-improved reference assembly.ConclusionsAFLAP can be used to generate high density linkage maps and improve genome assemblies of any organism when a mapping population is available using whole genome sequencing or genotyping-by-sequencing data. Genetic maps produced for B. lactucae were accurately aligned to the genome and guided significant improvements of the reference assembly.

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Identification of QTLs for Stripe Rust Resistance in a Recombinant Inbred Line Population

International Journal of Molecular Sciences ◽

10.3390/ijms20143410 ◽

2019 ◽

Vol 20 (14) ◽

pp. 3410 ◽

Cited By ~ 6

Author(s):

Manyu Yang ◽

Guangrong Li ◽

Hongshen Wan ◽

Liping Li ◽

Jun Li ◽

...

Keyword(s):

Genetic Map ◽

Stripe Rust ◽

Resistance Genes ◽

Phenotypic Variation ◽

Recombinant Inbred ◽

Rust Resistance ◽

High Density ◽

Genetic Maps ◽

Stripe Rust Resistance ◽

Resistance Locus

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating fungal diseases of wheat worldwide. It is essential to discover more sources of stripe rust resistance genes for wheat breeding programs. Specific locus amplified fragment sequencing (SLAF-seq) is a powerful tool for the construction of high-density genetic maps. In this study, a set of 200 recombinant inbred lines (RILs) derived from a cross between wheat cultivars Chuanmai 42 (CH42) and Chuanmai 55 (CH55) was used to construct a high-density genetic map and to identify quantitative trait loci (QTLs) for stripe rust resistance using SLAF-seq technology. A genetic map of 2828.51 cM, including 21 linkage groups, contained 6732 single nucleotide polymorphism markers (SNP). Resistance QTLs were identified on chromosomes 1B, 2A, and 7B; Qyr.saas-7B was derived from CH42, whereas Qyr.saas-1B and Qyr.saas-2A were from CH55. The physical location of Qyr.saas-1B, which explained 6.24–34.22% of the phenotypic variation, overlapped with the resistance gene Yr29. Qyr.saas-7B accounted for up to 20.64% of the phenotypic variation. Qyr.saas-2A, a minor QTL, was found to be a likely new stripe rust resistance locus. A significant additive effect was observed when all three QTLs were combined. The combined resistance genes could be of value in breeding wheat for stripe rust resistance.

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Construction of a high-resolution genetic map and identification of quantitative trait loci for salt tolerance in jute (Corchous spp.)

BMC Plant Biology ◽

10.1186/s12870-019-2004-7 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Zemao Yang ◽

Youxin Yang ◽

Zhigang Dai ◽

Dongwei Xie ◽

Qing Tang ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Qtl Mapping ◽

Genetic Map ◽

Quantitative Trait ◽

High Density ◽

Genetic Maps ◽

Interval Length ◽

Phenotypic Variance ◽

Qtls Mapping

Abstract Background Jute (Corchorus spp.) is the most important natural fiber crop after cotton in terms of cultivation area and production. Salt stress greatly restricts plant development and growth. A high-density genetic linkage map is the basis of quantitative trait locus (QTLs) mapping. Several high-density genetic maps and QTLs mapping related to salt tolerance have been developed through next-generation sequencing in many crop species. However, such studies are rare for jute. Only several low-density genetic maps have been constructed and no salt tolerance-related QTL has been mapped in jute to date. Results We developed a high-density genetic map with 4839 single nucleotide polymorphism markers spanning 1375.41 cM and an average distance of 0.28 cM between adjacent markers on seven linkage groups (LGs) using an F2 jute population, LGs ranged from LG2 with 299 markers spanning 113.66 cM to LG7 with 1542 markers spanning 350.18 cM. In addition, 99.57% of gaps between adjacent markers were less than 5 cM. Three obvious and 13 minor QTLs involved in salt tolerance were identified on four LGs explaining 0.58–19.61% of the phenotypic variance. The interval length of QTL mapping varied from 1.3 to 20.2 cM. The major QTL, qJST-1, was detected under two salt stress conditions that explained 11.81 and 19.61% of the phenotypic variation, respectively, and peaked at 19.3 cM on LG4. Conclusions We developed the first high-density and the most complete genetic map of jute to date using a genotyping-by-sequencing approach. The first QTL mapping related to salt tolerance was also carried out in jute. These results should provide useful resources for marker-assisted selection and transgenic breeding for salt tolerance at the germination stage in jute.

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Preliminary Genetic Map of a New Recombinant Inbred Line Population for Narrow-leafed Lupin (Lupinus angustifolius L.)

Agronomy ◽

10.3390/agronomy9100653 ◽

2019 ◽

Vol 9 (10) ◽

pp. 653 ◽

Cited By ~ 1

Author(s):

Bartosz Kozak ◽

Renata Galek ◽

Dariusz Zalewski ◽

Ewa Sawicka-Sienkiewicz

Keyword(s):

Genetic Map ◽

Genome Wide Association Study ◽

Reference Genome ◽

High Density ◽

Genetic Maps ◽

New Variety ◽

Model Legume ◽

Speed Up ◽

Trait Locus ◽

Next Generation Sequencing Ngs

Genetic maps are an essential tool for investigating molecular markers’ linkage with traits of agronomic importance. Breeders put a lot of emphasis on this type of markers, which are used in breeding programs implementation and speed up the process of a new variety development. In this paper, we construct a new, high-density linkage genetic map for Polish material on narrow-leafed lupin. The mapping population originated from crossing the Polish variety ‘Emir’ and the Belarusian breeding line ‘LAE-1’. A new map was constructed based on DArTseq markers—a new type of marker generated with the next-generation sequencing (NGS) technique. The map was built with 4602 markers, which are divided into 20 linkage groups, corresponding with the number of gametic chromosomes in narrow-leafed lupin. On the new map there are 1174 unique loci. The total length of all linkage group is 3042 cM. This map was compared to the reference genome of narrow-leafed lupin and the CDS sequence for model legume species: emphMedicago truncatula, emphLotus japonicus and Glycine max. Analysis revealed the presence of the DArTseq marker common for all investigated species. We were able to map 38 new, unplaced scaffolds on the new genetic map of narrow-leafed lupin. The high-density genetic map we received can be used for quantitative trait locus (QTL) mapping, genome-wide association study analysis and assembly of the reference genome for the whole genome sequencing (WGS) method

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Quantitative Trait Locus (QTLs) Mapping for Quality Traits of Wheat Based on High Density Genetic Map Combined With Bulked Segregant Analysis RNA-seq (BSR-Seq) Indicates That the Basic 7S Globulin Gene Is Related to Falling Number

Frontiers in Plant Science ◽

10.3389/fpls.2020.600788 ◽

2020 ◽

Vol 11 ◽

Author(s):

Qiao Li ◽

Zhifen Pan ◽

Yuan Gao ◽

Tao Li ◽

Junjun Liang ◽

...

Keyword(s):

Genetic Map ◽

Quantitative Trait ◽

Recombinant Inbred Lines ◽

High Density ◽

Genetic Maps ◽

Phenotypic Variance ◽

Quality Traits ◽

Rna Seq ◽

Falling Number ◽

7S Globulin

Numerous quantitative trait loci (QTLs) have been identified for wheat quality; however, most are confined to low-density genetic maps. In this study, based on specific-locus amplified fragment sequencing (SLAF-seq), a high-density genetic map was constructed with 193 recombinant inbred lines derived from Chuanmai 42 and Chuanmai 39. In total, 30 QTLs with phenotypic variance explained (PVE) up to 47.99% were identified for falling number (FN), grain protein content (GPC), grain hardness (GH), and starch pasting properties across three environments. Five NAM genes closely adjacent to QGPC.cib-4A probably have effects on GPC. QGH.cib-5D was the only one detected for GH with high PVE of 33.31–47.99% across the three environments and was assumed to be related to the nearest pina-D1 and pinb-D1genes. Three QTLs were identified for FN in at least two environments, of which QFN.cib-3D had relatively higher PVE of 16.58–25.74%. The positive effect of QFN.cib-3D for high FN was verified in a double-haploid population derived from Chuanmai 42 × Kechengmai 4. The combination of these QTLs has a considerable effect on increasing FN. The transcript levels of Basic 7S globulin and Basic 7S globulin 2 in QFN.cib-3D were significantly different between low FN and high FN bulks, as observed through bulk segregant RNA-seq (BSR). These QTLs and candidate genes based on the high-density genetic map would be beneficial for further understanding of the genetic mechanism of quality traits and molecular breeding of wheat.

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Genetic mapping studies in Coffea sp using molecular marker methods Studi peta genetik pada Coffea sp. menggunakan metode penanda molekuler

E-Journal Menara Perkebunan ◽

10.22302/iribb.jur.mp.v83i2.6 ◽

2016 ◽

Vol 83 (2) ◽

Author(s):

. PRIYONO ◽

Riza Arief PUTRANTO

Keyword(s):

Molecular Markers ◽

Genetic Mapping ◽

Genetic Map ◽

Crop Improvement ◽

Average Density ◽

Genetic Maps ◽

Gene Characterization ◽

Robusta Coffee ◽

Dna And Rna ◽

Genomic Comparative Analysis

AbstrakAnalisis genetik telah menjadi alat yang penting dalam pemuliaan tanaman untuk perbaikan sifat penting tanaman. Salah satu potensi terbesar dari analisis tersebut adalah identifikasi penanda molekuler yang berguna untuk pemetaan genetik. Pemetaan genetik merupakan salah satu langkah penting dari analisis genetik. Intisari dari semua pemetaan genetik adalah menempatkan koleksi pe- nanda molekuler pada posisi tertentu dalam genom. Hal tersebut dapat kemudian digunakan untuk meng- identifikasi lokus sifat kuantitatif (QTLs) dengan memanfaatan keragaman genetik alami yang tersedia dan meningkatkan sifat-sifat penting serta berharga. Sampai saat ini, tiga belas peta genetik telah dipublikasi dan tersedia pada Coffea sp. yang menciptakan database besar untuk kerangka genetik. Sebuah peta genetik terbaru dengan akses terbuka dan berfungsi sebagai referensi telah dibangun oleh International Coffee Genomics Network (ICGN). Peta tersebut tediri dari 3230 lokus, dengan panjang peta 1471 cM (1cm ~ 500 Kb) serta kepadatan satu penanda setiap 220 Kb. Peta-peta genetik pada tanaman kopi telah digunakan dari karakterisasi gen hingga analisis komparatif genom dengan spesies tanaman yang berbeda. Saat ini, pesatnya kemajuan teknologi New Genome Sequencing (NGS) untuk sekuensing DNA dan RNA memungkinkan validasi dari peta-peta genetik untuk prediksi QTLs serta gen-gen yang membawa sifat penting Coffea sp.AbstractGenetic analysis has become an important tool in plant breeding for crop improvement. One of their greatest potential appears to be the identification of molecular markers useful for genetic mapping. Genetic mapping is one of important steps in genetic analysis. The essence of all genetic mapping is to place a collection of molecular markers onto their respective positions on the genome. Thus, it leads to identification of new quantitative trait loci (QTLs) by making benefits of natural available genetic diversity.and to improve important and valuable traits. Until present, thirteen genetic maps were published and available in Coffea sp. creating a huge database for genetic framework. One most recent and open reference genetic map for robusta coffee has been generated by the International Coffee Genomics Network (ICGN) comprising 3230 loci, genetic size 1471 cM (1cM ~500 Kb), with an average density close to one marker every 220 Kb. The Coffea genetic maps have been utilized from gene characterization to genomic comparative analysis with different plant species. Nowadays, the feasibility of NGS for DNA and RNA sequencing allow the validation of genetic map related to the prediction of QTLs and adjacent genes related to important traits for Coffea sp.

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Identify of Fast-Growing Related Genes Especially in Height Growth by Combining QTL Analysis and Transcriptome in Salix matsudana (Koidz)

Frontiers in Genetics ◽

10.3389/fgene.2021.596749 ◽

2021 ◽

Vol 12 ◽

Author(s):

Guoyuan Liu ◽

Qingshan Yang ◽

Junfeng Gao ◽

Yuwei Wu ◽

Zhicong Feng ◽

...

Keyword(s):

Genetic Map ◽

Genetic Regulation ◽

Lignin Biosynthesis ◽

Principal Component ◽

Height Growth ◽

High Density ◽

Genetic Maps ◽

Pcr Analysis ◽

Total Size ◽

Fast Growing

The study on the fast-growing traits of trees, mainly valued by tree height (TH) and diameter at breast height (DBH), is of great significance to promote the development of the forest industry. Quantitative trait locus (QTL) mapping based on high-density genetic maps is an efficient approach to identify genetic regions for fast-growing traits. In our study, a high-density genetic map for the F1 population was constructed. The genetic map had a total size of 5,484.07 centimorgan (cM), containing 5,956 single nucleotide polymorphisms (SNPs) based on Specific Length Amplified Fragment sequencing. Six fast-growing related stable QTL were identified on six chromosomes, and five stable QTL were identified by a principal component analysis (PCA). By combining the RNA-seq analysis for the two parents and two progenies with the qRT-PCR analysis, four candidate genes, annotated as DnaJ, 1-aminocyclopropane-1-carboxylate oxidase 1 (ACO1), Caffeic acid 3-O-methyltransferase 1 (COMT1), and Dirigent protein 6 (DIR6), that may regulate height growth were identified. Several lignin biosynthesis-related genes that may take part in height growth were detected. In addition, 21 hotspots in this population were found. The results of this study will provide an important foundation for further studies on the molecular and genetic regulation of TH and DBH.

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