Correlating the Genetic and Physical Map of Barley Chromosome 3H Revealed Limitations of the FISH-Based Mapping of Nearby Single-Copy Probes Caused by the Dynamic Structure of Metaphase Chromosomes

2017 ◽  
Vol 152 (2) ◽  
pp. 90-96 ◽  
Author(s):  
Fernanda O. Bustamante ◽  
Lala Aliyeva-Schnorr ◽  
Jörg Fuchs ◽  
Sebastian Beier ◽  
Andreas Houben

Genetic maps are based on the recombination frequency of molecular markers which often show different positions in comparison to the corresponding physical maps. To decipher the position and order of DNA sequences genetically mapped to terminal and interstitial regions of barley (Hordeum vulgare) chromosome 3H, fluorescence in situ hybridization (FISH) on mitotic metaphase chromosomes was performed with 16 genomic single-copy probes derived from fingerprinted BAC contigs. Long genetic distances at subterminal regions translated into short physical distances, confirming that recombination events occur more often at distal regions of chromosome 3H. Nonoverlapping FISH signals were frequently obtained for probes with a physical distance of at least 30-60 kb. Only 8% of the analyzed chromosomes showed a symmetric order of FISH signals on both sister chromatids. Due to the dynamic packing of metaphase chromatin, the order of 2 adjacent single-copy signals along the chromosome arms outside the (peri)centromeric region can only reliably be determined if the cytological distance is approximately 3%, corresponding to 21.6 Mb.

Author(s):  
Barbara J. F. Trask ◽  
Hillary Massa ◽  
Cynthia Friedman ◽  
Richard Esposito ◽  
Ger van den Engh ◽  
...  

The sites of specific DNA sequences can be fluorescently tagged by fluorescence in situ hybridization (FISH). Different sequences can be labeled with different fluorochromes so that their arrangement can be studied using epifluorescence microscopy. The distances between points on the same or different chromosomes can be determined easily in a large number of interphase nuclei or metaphase chromosomes. A variety of probe types, ranging from single-copy sequences to highly repeated sequences can be employed. Our work has focussed on the analysis of hybridization patterns in two dimensions using conventional fluorescence microscopy.We have used FISH to study various aspects of genome organization that are difficult to study using other techniques. Examples of these applications will be presented.FISH is now the method of choice for determining the chromosomal location of DNA sequences. DNA sequences can be positioned in the genome with <1:1000 accuracy (to a 3-Mbp region within a 3000-Mbp genome). Through FISH, the cytogenetic, physical and genetic maps of chromosomes can be linked.


Author(s):  
B. A. Hamkalo ◽  
Elizabeth R. Unger

This symposium brings together several approaches for the detection of specific nucleic acid sequences that have potential applications at the histochemical level.Trask et al. report on the use of fluorescence in situ hybridization (FISH) techniques to study the arrangement of DNA sequences in normal and diseaserelated chromosomes. The sites of specific DNA sequences can be fluorescently tagged. Different sequences can be labeled with different fluorochromes so that their arrangement can be studied using fluorescence microscopy. The distances between points on the same or different chromosomes can be determined in a large number of interphase nuclei or metaphase chromosomes. A variety of probe types, ranging from single-copy sequences to highly repeated sequences can be employed.Hamkalo and co-workers have used non-radioactive methods at the EM level for the detection of nucleic acid sequences by in situ hybridization. Analysis of metaphase chromosomes by electron microscopy allows for high resolution mapping of chromosomes. A variety of labelling procedures have been employed to illustrate the utility of high resolution nucleic acid sequence mapping in these preparations.


Genome ◽  
1994 ◽  
Vol 37 (5) ◽  
pp. 717-725 ◽  
Author(s):  
Jiming Jiang ◽  
Bikram S. Gill

Nonisotopic in situ hybridization (ISH) was introduced in plants in 1985. Since then the technique has been widely used in various areas of plant genome mapping. ISH has become a routine method for physical mapping of repetitive DNA sequences and multicopy gene families. ISH patterns on somatic metaphase chromosomes using tandemly repeated sequences provide excellent physical markers for chromosome identification. Detection of low or single copy sequences were also reported. Genomic in situ hybridization (GISH) was successfully used to analyze the chromosome structure and evolution of allopolyploid species. GISH also provides a powerful technique for monitoring chromatin introgession during interspecific hybridization. A sequential chromosome banding and ISH technique was developed. The sequential technique is very useful for more precise and efficient mapping as well as cytogenetic determination of genomic affinities of individual chromosomes in allopolyploid species. A critical review is made on the present resolution of the ISH technique and the future outlook of ISH research is discussed.Key words: in situ hybridization, physical mapping, genome mapping, molecular cytogenetics.


Genetics ◽  
1999 ◽  
Vol 152 (1) ◽  
pp. 427-439 ◽  
Author(s):  
Daniel G Peterson ◽  
Nora L V Lapitan ◽  
Stephen M Stack

Abstract Fluorescence in situ hybridization (FISH) is a powerful means by which single- and low-copy DNA sequences can be localized on chromosomes. Compared to the mitotic metaphase chromosomes that are normally used in FISH, synaptonemal complex (SC) spreads (hypotonically spread pachytene chromosomes) have several advantages. SC spreads (1) are comparatively free of debris that can interfere with probe penetration, (2) have relatively decondensed chromatin that is highly accessible to probes, and (3) are about ten times longer than their metaphase counterparts, which permits FISH mapping at higher resolution. To investigate the use of plant SC spreads as substrates for single-copy FISH, we probed spreads of tomato SCs with two single-copy sequences and one low-copy sequence (ca. 14 kb each) that are associated with restriction fragment length polymorphism (RFLP) markers on SC 11. Individual SCs were identified on the basis of relative length, arm ratio, and differential staining patterns after combined propidium iodide (PI) and 4′,6-diamidino-2-phenylindole (DAPI) staining. In this first report of single-copy FISH to SC spreads, the probe sequences were unambiguously mapped on the long arm of tomato SC 11. Coupled with data from earlier studies, we determined the distance in micrometers, the number of base pairs, and the rates of crossing over between these three FISH markers. We also observed that the order of two of the FISH markers is reversed in relation to their order on the molecular linkage map. SC-FISH mapping permits superimposition of markers from molecular linkage maps directly on pachytene chromosomes and thereby contributes to our understanding of the relationship between chromosome structure, gene activity, and recombination.


Author(s):  
Barbara Trask ◽  
Susan Allen ◽  
Anne Bergmann ◽  
Mari Christensen ◽  
Anne Fertitta ◽  
...  

Using fluorescence in situ hybridization (FISH), the positions of DNA sequences can be discretely marked with a fluorescent spot. The efficiency of marking DNA sequences of the size cloned in cosmids is 90-95%, and the fluorescent spots produced after FISH are ≈0.3 μm in diameter. Sites of two sequences can be distinguished using two-color FISH. Different reporter molecules, such as biotin or digoxigenin, are incorporated into DNA sequence probes by nick translation. These reporter molecules are labeled after hybridization with different fluorochromes, e.g., FITC and Texas Red. The development of dual band pass filters (Chromatechnology) allows these fluorochromes to be photographed simultaneously without registration shift.


Genetics ◽  
1996 ◽  
Vol 142 (2) ◽  
pp. 537-548 ◽  
Author(s):  
Michael W Nachman ◽  
Gary A Churchill

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.


2011 ◽  
Vol 30 (9) ◽  
pp. 1779-1786 ◽  
Author(s):  
Kun Yang ◽  
Hecui Zhang ◽  
Richard Converse ◽  
Yong Wang ◽  
Xiaoying Rong ◽  
...  

1982 ◽  
Vol 2 (1) ◽  
pp. 52-65 ◽  
Author(s):  
O W McBride ◽  
A S Olsen ◽  
G S Aulakh ◽  
R S Athwal

Transfer of genetic information can be effected by incubation of cultured eucaryotic cells with isolated metaphase chromosomes. In most cases, a resulting transformed cell contains only a fragment of a donor chromosome. The amount of transferred donor DNA has been quantified in 11 independent mouse A9 transformants by nucleic acid hybridization analysis. Each transformant had been selected for hprt (hypoxanthine phosphoribosyltransferase; EC 2.4.2.8) transfer and contained part of the human X chromosome. A labeled probe of transcribed human X-chromosomal DNA was prepared by hybridization of nick-translated unique-sequence human DNA with whole cellular RNA from a human-mouse hybrid cell line, A9/HRBC2-A, containing a single human chromosome., X. The amount of human X-chromosomal DNA in the transformants was quantitated by comparing the hybridization of this probe with transformant and A9/HRBC2-A DNAs. Two unstable transformants which had a microscopically detectable donor chromosome fragment contained 15% of the human X-chromosomal single-copy DNA. Four other unstable transformants contained 4 to 7% of human X-chromosomal DNA sequences. The transferred DNA was below the level of detection in three other unstable and in all three stable transformants. We conclude that the initial transfer event can introduce a substantial amount of genetic information but only smaller amounts of DNA are stably incorporated by integration.


Sign in / Sign up

Export Citation Format

Share Document