AFLP and SSR polymorphism in a Coffea interspecific backcross progeny [(C. heterocalyx × C. canephora) × C. canephora]

ABSTRACT The products of 49 protein-coding loci were examined by starch gel electrophoresis for populational variation in six species of Xiphophorus fishes and/or segregation in intra- and interspecific backcross and intercross hybrids. Electrophoretic variation was observed for 29 of the 35 locus products in a survey of 42 population samples. The highest frequency of polymorphic loci observed in noninbred populations was 0.143. After ten or more generations of inbreeding, all loci studied were monomorphic. Inbred strains generally exhibited the commonest electrophoretic alleles of the population from which they were derived. An assessment of genetic distances among Xiphophorus populations reflected classical systematic relationships and suggested incipient subspeciation between X. maculatus from different drainages as well as several species groups. Thirty-three loci were analyzed with respect to segregation in hybrids. The goodness of fit of segregations to Mendelian expectations at all loci analyzed (except loci in linkage group I) is interpreted as evidence for high genetic compatibility of the genomes of Xiphophorus species. It is anticipated that these data will result in a rapid expansion of the assignment of protein-coding loci to linkage groups in these lower vertebrate species.

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Recombinant inbred strain and interspecific backcross analysis of molecular markers flanking the murine agouti coat color locus.

Genetics ◽

10.1093/genetics/122.3.669 ◽

1989 ◽

Vol 122 (3) ◽

pp. 669-679

Author(s):

L D Siracusa ◽

A M Buchberg ◽

N G Copeland ◽

N A Jenkins

Keyword(s):

Molecular Markers ◽

Inbred Strain ◽

Mouse Chromosome ◽

Recombinant Inbred ◽

Recombinant Inbred Strain ◽

Interspecific Backcross ◽

Chromosome 2 ◽

Chromosome 4 ◽

Agouti Locus ◽

Mouse Chromosome 2

Abstract Recombinant inbred strain and interspecific backcross mice were used to create a molecular genetic linkage map of the distal portion of mouse chromosome 2. The orientation and distance of the Ada, Emv-13, Emv-15, Hck-1, Il-1a, Pck-1, Psp, Src-1 and Svp-1 loci from the beta 2-microglobulin locus and the agouti locus were established. Our mapping results have provided the identification of molecular markers both proximal and distal to the agouti locus. The recombinants obtained provide valuable resources for determining the direction of chromosome walking experiments designed to clone sequences at the agouti locus. Comparisons between the mouse and human genome maps suggest that the human homolog of the agouti locus resides on human chromosome 20q. Three loci not present on mouse chromosome 2 were also identified and were provisionally named Psp-2, Hck-2 and Hck-3. The Psp-2 locus maps to mouse chromosome 14. The Hck-2 locus maps near the centromere of mouse chromosome 4 and may identify the Lyn locus. The Hck-3 locus maps near the distal end of mouse chromosome 4 and may identify the Lck locus.

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Anchoring a genetic map of an interspecific backcross two family to the genome builds of Elaeis

Journal of Genetics ◽

10.1007/s12041-020-01240-8 ◽

2021 ◽

Vol 100 (1) ◽

Author(s):

KATIALISA KAMARUDDIN ◽

MAIZURA ITHNIN ◽

NGOOT-CHIN TING ◽

ZULKIFLI YAAKUB ◽

NIK SHAZANA NIK MOHD SANUSI ◽

...

Keyword(s):

Genetic Map ◽

Interspecific Backcross

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Murine Albino-Deletion Complex: High-Resolution Microsatellite Map and Genetically Anchored YAC Framework Map

Genetics ◽

10.1093/genetics/147.2.787 ◽

1997 ◽

Vol 147 (2) ◽

pp. 787-799

Author(s):

Brad A Rikke ◽

Dabney K Johnson ◽

Thomas E Johnson

Keyword(s):

Positional Cloning ◽

Interspecific Backcross ◽

Genetic Distances ◽

Sequence Length ◽

Recombination Rates ◽

Oak Ridge ◽

Artificial Chromosomes ◽

Microsatellite Map ◽

Specific Locus ◽

Yeast Artificial Chromosomes

The murine albino-deletion complex developed as part of the Oak Ridge specific-locus test covers 6–11 cM of chromosome 7. This complex has proven to be a valuable resource for localizing traits to a small target region suitable for positional cloning. In this study, we mapped the endpoints of deletions in this complex using all of the available Mit simple-sequence length polymorphism (SSLP) markers. Concurrently, this mapping has determined the map order of nearly all of the SSLP markers, most of which were previously unresolved. The SSLP-based deletion map was confirmed and genetic distances were determined using the European Collaborative Interspecific Backcross panel of nearly a thousand mice. The average SSLP marker resolution is 0.3–0.4 cM, comparable to the cloning capacity of yeast artificial chromosomes (YACs). The SSLP markers were then used to construct a genetically anchored YAC framework map that further confirms the deletion map. We find that the largest deleted region distal to Tyr is about two to three times larger than the largest proximal deleted region, and the original C3H/101 regions flanking the deletions (moved to an St2A cch/cch background) are smaller than anticipated, which we suggest may result from increased recombination rates immediately flanking the deleted regions.

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Bayesian Mapping of Multiple Quantitative Trait Loci From Incomplete Inbred Line Cross Data

Genetics ◽

10.1093/genetics/148.3.1373 ◽

1998 ◽

Vol 148 (3) ◽

pp. 1373-1388

Author(s):

Mikko J Sillanpää ◽

Elja Arjas

Keyword(s):

Quantitative Trait Loci ◽

Quantitative Trait ◽

Composite Interval Mapping ◽

Backcross Progeny ◽

Random Variable ◽

Interval Mapping ◽

Mapping Method ◽

Structure Mapping ◽

Standard Interval ◽

Trait Loci

Abstract A novel fine structure mapping method for quantitative traits is presented. It is based on Bayesian modeling and inference, treating the number of quantitative trait loci (QTLs) as an unobserved random variable and using ideas similar to composite interval mapping to account for the effects of QTLs in other chromosomes. The method is introduced for inbred lines and it can be applied also in situations involving frequent missing genotypes. We propose that two new probabilistic measures be used to summarize the results from the statistical analysis: (1) the (posterior) QTL-intensity, for estimating the number of QTLs in a chromosome and for localizing them into some particular chromosomal regions, and (2) the location wise (posterior) distributions of the phenotypic effects of the QTLs. Both these measures will be viewed as functions of the putative QTL locus, over the marker range in the linkage group. The method is tested and compared with standard interval and composite interval mapping techniques by using simulated backcross progeny data. It is implemented as a software package. Its initial version is freely available for research purposes under the name Multimapper at URL http://www.rni.helsinki.fi/~mjs.

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