共查询到20条相似文献,搜索用时 15 毫秒
1.
Okaama I. Dukhanina Howard Dene Alan Y. Deng Carol R. Choi Barbara Hoebee John P. Rapp 《Mammalian genome》1997,8(4):229-235
Our purposes were to develop a linkage map for rat Chromosome (Chr) 10, using chromosome-sorted DNA, and to construct congenic
strains to localize blood pressure quantitative trait loci (QTL) on Chr 10 with the map. The linkage mapping panel consisted
of three F2 populations totaling 418 rats. Thirty-two new and 29 known microsatellite markers were placed on the map, which spanned 88.9
centiMorgans (cM). The average distance between markers was 1.46 cM. No markers were separated by more than 6.8 cM. Four congenic
strains were constructed by introgressing various segments of Chr 10 from the Milan normotensive strain (MNS) onto the background
of the Dahl salt-sensitive (S) strain. A blood pressure QTL with a strong effect on blood pressure (35–42 mm Hg) when expressed
on the S background was localized to a 31-cM region between D10Mco6 and D10Mcol. The region does not include the locus for inducible nitric oxide synthase (Nos2), which had been considered to be a candidate locus for the QTL.
Received: 25 September 1996 / Accepted: 9 November 1996 相似文献
2.
Oksana I. Dukhanina Vladimir E. Sverdlov Barbara Hoebee John P. Rapp 《Mammalian genome》1999,10(1):26-29
An improved linkage map for rat Chromosome (Chr) 10 with two F2 populations was constructed. Thirty new microsatellite markers were generated from a Chr 10-specific, small-insert genomic
library and mapped to rat Chr 10. Among them were the rat homologs for the mouse gene for light and heavy chains of myeloperoxidase
and human neurofibromatosis 1. Eight newly generated markers (D10Mco62, D10Mco63, D10Mco64, D10Mco65, D10Mco67, D10Mco68, D10Mco70, and D10Mco74) were mapped to the region of the rat Chr 10 blood pressure QTL. The availability of such markers may be instrumental in
the search for genes responsible for the hypertension.
Received: 13 July 1998 / Accepted: 9 September 1998 相似文献
3.
A second-generation linkage map of the sheep genome 总被引:32,自引:0,他引:32
Maurico J. de Gortari Brad A. Freking Rachel P. Cuthbertson Steven M. Kappes John W. Keele Roger T. Stone Kreg A. Leymaster Ken G. Dodds Allan M. Crawford Craig W. Beattie 《Mammalian genome》1998,9(3):204-209
A genetic map of Ovis aries (haploid n = 27) was developed with 519 markers (504 microsatellites) spanning ∼3063 cM in 26 autosomal linkage groups and
127 cM (female specific) of the X Chromosome (Chr). Genotypic data were merged from the IMF flock (Crawford et al., Genetics
140, 703, 1995) and the USDA mapping flock. Seventy-three percent (370/504) of the microsatellite markers on the map are common
to the USDA-ARS MARC cattle linkage map, with 27 of the common markers derived from sheep. The number of common markers per
homologous linkage group ranges from 5 to 22 and spans a total of 2866 cM (sex average) in sheep and 2817 cM in cattle. Marker
order within a linkage group was consistent between the two species with limited exceptions. The reported translocation between
the telomeric end of bovine Chr 9 (BTA 9) and BTA 14 to form ovine Chr 9 is represented by a 15-cM region containing 5 common
markers. The significant genomic conservation of marker order will allow use of linkage maps in both species to facilitate
the search for quantitative trait loci (QTLs) in cattle and sheep.
Received: 20 September 1992 / Accepted: 18 November 1997 相似文献
4.
Q. Y. Zhang H. Dene A. Y. Deng M. R. Garrett H. J. Jacob J. P. Rapp 《Mammalian genome》1997,8(9):636-641
The renin locus (Ren) on rat Chromosome (Chr) 13 had previously been shown to cosegregate with blood pressure in crosses involving Dahl salt-sensitive
(S) and Dahl salt-resistant (R) rats. In the present work, interval mapping of blood pressure on Chr 13 with a large F2 (S × R), n = 233, population yielded a maximum LOD = 4.2 for linkage to blood pressure, but the quantitative trait locus
(QTL) was only poorly localized to a large 35-centiMorgan (cM) segment of Chr 13. In the linkage analysis, the S-rat QTL allele
(S) was associated with higher, and the R-rat QTL allele (R) with lower blood pressure, the difference between homozygotes being about 20 mm Hg. A congenic strain was made by introgressing
the R-rat Ren allele into the recipient S strain. This congenic strain showed a 24 mm Hg reduction (P = 0.004) in blood pressure compared
with S rats for rats fed 2% NaCl diet for 24 days; this difference was confirmed by two other independent tests. Two congenic
substrains were derived from the first congenic strain with shorter R Chr 13 segments on the S background. Comparisons among
these congenic strains showed that a blood pressure QTL was in the 24-cM chromosomal segment between Syt2 and D13M1Mit108. This segment does not include the renin locus, which is thus excluded from being the gene on rat Chr 13 responsible for genetic
differences in blood pressure detected by linkage analysis.
Received: 20 December 1996 / Accepted: 7 April 1997 相似文献
5.
Construction of an RAPD linkage map and localization of QTLs for oleic acid level using recombinant inbreds in mustard (Brassica juncea). 总被引:1,自引:0,他引:1
RAPD markers were employed for construction of a linkage map and localization of QTLs for oleic acid level using a set of 94 recombinant inbred lines (RILs) of mustard (Brassica juncea L.) as a mapping population. Only 30% of the 235 random primers used were useful in terms of polymorphism detected and the reproducibility of those patterns. Normal Mendelian segregation was observed for the majority of the 130 markers obtained with 71 informative primers; only 13.1% deviated (P < 0.01) from the expected 1:1 ratio. One-hundred and fourteen markers were assigned to 21 linkage groups (LGs) covering a total length of 790.4 cM with an average distance of 6.93 cM between markers. Two quantitative trait loci (QTL) for oleic acid level were mapped to 14- and 10.6-cM marker intervals on two different LGs. Both loci together explained 32.2% of phenotypic variance. One major QTL explained 28.5% of the trait variance observed in this species. 相似文献
6.
Quantitative trait loci (QTLs) affecting body weight were investigated in the backcross population derived from nondiabetic
BB/OK and spontaneously hypertensive rat (SHR) strains. The F1 hybrids were backcrossed onto SHR rats, and QTL analysis was performed separately with the resulting backcross populations
for each sex on Chromosomes (Chrs) 1, 3, 4, 10, 13, and 18. The body weight was determined at the age of 14 weeks, and the
statistical analysis was performed with MAPMAKER/QTL 1.1b computer program. According to the stringent threshold for a lod
score of 3.0, markers on Chr 1 were found to be linked with body weight. The QTL with a peak lod score (5.1) on Chr 1 for
a male population was located within markers Igf2 and D1Mgh12. In contrast, in the female population the body weight affecting QTL (lod = 5.7) on Chr 1 was located between the D1Mit3 and Lsn markers. The existence of QTLs on Chr 1 affecting body weight in the male population was confirmed by congenic BB.Sa rats,
carrying chromosomal region of SHR (Sa-Igf2) on the genetic background of BB rat.
Received: 14 July 1997 / Accepted: 22 December 1997 相似文献
7.
8.
Paula Bice Tatiana Foroud Ronghai Bo Peter Castelluccio Lawrence Lumeng Ting-Kai Li Lucinda G. Carr 《Mammalian genome》1998,9(12):949-955
Selective breeding for voluntary alcohol consumption was utilized to establish the alcohol-preferring (P) and alcohol-nonpreferring
(NP) rat lines. Inbreeding was initiated after 30 generations of selection and, after 19 generations of inbreeding, 384 F2 intercross progeny were created to identify quantitative trait loci (QTLs) influencing alcohol consumption. We had reported
previously a QTL on Chromosome (Chr) 4; additional markers genotyped on Chr 4 have increased the maximum lod score from 8.6
to 9.2. This QTL acts in an additive fashion and continues to account for approximately 11% of the phenotypic variability.
The 95% confidence interval is 12.5 cM and includes the candidate gene, neuropeptide Y. Subsequent to the identification of
the QTL on Chr 4, a genome scan was completed to identify additional QTLs influencing alcohol consumption. A lod score of
2.5 was obtained on Chr 3, syntenic to a region previously reported for alcohol preference in mice. Analysis of Chr 8 produced
a lod score of 2.2 near the dopamine D2 and serotonin 1b receptors, which have been previously reported as candidate genes
for alcohol preference. Evidence for linkage to alcohol consumption was not found on any other chromosome. It therefore appears
likely that, in addition to the QTL on Chr 4, multiple loci of small to moderate effect, such as those on Chrs 3 and 8, underlie
the difference in alcohol consumption in the P/NP lines.
Received: 15 September 1998 / Accepted: 8 October 1998 相似文献
9.
A region on rat Chromosome (Chr) 2 of the Dahl salt-sensitive rat (S) was shown previously to contain a quantitative trait
locus (QTL) for blood pressure (BP). This was achieved first by linkage, followed by the use of congenic strains. A congenic
strain, designated S.MNS-D2Mit6/Adh, contained a segment of Chr 2 from the Milan Normotensive (MNS) rat in the S genetic background. Since the region containing
the QTL was roughly 80 cM in size, a further reduction was needed towards the positional or candidate gene cloning. Currently,
two congenic substrains were made from the original strain S.MNS-D2Mit6/Adh. One of these two substrains showed a BP-lowering effect, whereas the other substrain did not. Deducing the segment not shared
in the two substrains, the BP QTL has to be present in a chromosome region of roughly 5.7 cM between the marker D2Rat303 and the locus for the neutroendopeptidase gene (Nep). Nep is not included within the segment. This region does not seem to contain any candidate genes well known for the BP control.
Thus, the final identification of the QTL will most likely lead to the discovery of a brand new gene for the BP regulation.
Received: 14 December 2000 / Accepted: 18 January 2001 相似文献
10.
T. Agui T. Miyamoto C.-G. Jung T. Tsumagari K. Masuda T. Manabe 《Mammalian genome》2000,11(10):862-865
The LEC rat has been reported to exhibit X-ray hypersensitivity and deficiency in DNA double-strand break (DSB) repair. The
present study was performed to map the locus responsible for this phenotype, the xhs (X-ray hypersensitivity), as the first step in identifying the responsible gene. Analysis of the progeny of (BN × LEC)F1× LEC backcrosses indicated that the X-ray hypersensitive phenotype was controlled by multiple genetic loci in contrast to
the results reported previously. Quantitative trait loci (QTL) linkage analysis revealed two responsible loci located on Chromosomes
(Chr) 4 and 1. QTL on Chr 4 exhibited very strong linkage to the X-ray hypersensitive phenotype, while QTL on Chr 1 showed
weak linkage. The Rad52 locus, mutation of which results in hypersensitivity to ionizing radiation and impairment of DNA DSB repair in yeast, was
reported to be located on the synteneic regions of mouse Chr 6 and human Chr 12. However, mapping of the rat Rad52 locus indicated that it was located 23 cM distal to the QTL on Chr 4. Furthermore, none of the radio-sensitivity-related
loci mapped previously in the rat chromosome were identical to the QTL on Chrs 4 and 1 in the LEC rat. Thus, it seems that
X-ray hypersensitivity in the LEC rat is caused by mutation(s) in as-yet-undefined genes.
Received: 14 February 2000 / Accepted: 17 May 2000 相似文献
11.
Vladimir E. Sverdlov Oksana I. Dukhanina Barbara Hoebee John P. Rapp 《Mammalian genome》1998,9(10):816-821
Fifty-eight new anonymous simple sequence repeats (SSR) were generated and mapped to various rat chromosomes. Among them
two genes (rat homologs for human cadherin-14 and mouse fibroblast growth factor-related protein) were mapped on Chromosomes
(Chrs) 2 and 11 respectively. The majority of markers were generated from a small insert genomic library specific to Chr 11,
13, 14, and 15. Twenty new markers were mapped to Chr 13, which is known to contain a blood pressure quantitative trait locus
(QTL). Several approaches to obtain microsatellite markers are described. The protocols and newly generated markers should
be useful for ongoing rat genome project.
Received: 24 April 1998 / Accepted: 23 June 1998 相似文献
12.
Quantitative trait loci for baseline white blood cell count, platelet count, and mean platelet volume 总被引:3,自引:0,他引:3
Luanne L. Peters Weidong Zhang Amy J. Lambert Carlo Brugnara Gary A. Churchill Orah S. Platt 《Mammalian genome》2005,16(10):749-763
A substantial genetic contribution to baseline peripheral blood counts has been established. We performed quantitative trait
locus/loci (QTL) analyses to identify chromosome (Chr) regions harboring genes influencing the baseline white blood cell (WBC)
count, platelet (Plt) count, and mean platelet volume (MPV) in F2 intercrosses between NZW/LacJ, SM/J, and C57BLKS/J inbred mice. We identified six significant WBC QTL: Wbcq1 (peak LOD score at 38 cM, Chr 1), Wbcq2 (42 cM, Chr 3), Wbcq3 (0 cM, Chr 15), Wbcq4 (58 cM, Chr 1), Wbcq5 (82 cM, Chr 1), and Wbcq6 (8 cM, Chr 14). Three significant Plt QTL were identified: Pltq1 (24 cM, Chr 2), Pltq2 (36 cM, Chr 7), and Pltq3 (10 cM, Chr 12). Two significant MPV QTL were identified, Mpvq1 (62 cM, Chr 15) and Mpvq2 (44 cM, Chr 8). In total, the WBC QTL accounted for up to 31% of the total variance in baseline WBC count, while the Plt
and MPV QTL accounted for up to 30% and 49% of the total variance, respectively. These analyses underscore the genetic complexity
underlying these traits in normal populations and provide the basis for future studies to identify novel genes involved in
the regulation of mammalian hematopoiesis. 相似文献
13.
Fine mapping and imprinting analysis for fatness trait QTLs in pigs 总被引:10,自引:0,他引:10
Annemieke P. Rattink Dirk J. De Koning Marilyne Faivre Barbara Harlizius Johan A.M. van Arendonk Martien A.M. Groenen 《Mammalian genome》2000,11(8):656-661
Quantitative trait loci (QTL) for fatness traits were reported recently in an experimental Meishan × Large White and Landrace
F2 cross. To further investigate the regions on pig Chr 2 (SSC2), SSC4, and SSC7, 25 additional markers from these regions were
typed on 800 animals (619 F2 animals, their F1 parents, and F0 grandfathers). Compared with the published maps, a modified order of markers was observed for SSC4 and SSC7. QTL analyses
were performed both within the half-sib families as well as across families (line cross). Furthermore, a QTL model accounting
for imprinting effects was tested. Information content could be increased considerably on all three chromosomes. Evidence
for the backfat thickness QTL on SSC7 was increased, and the location could be reduced to a 33-cM confidence interval. The
QTL for intramuscular fat on SSC4 could not be detected in this half-sib analysis, whereas under the line cross model a suggestive
QTL on a different position on SSC4 was detected. For SSC2, in the half-sib analysis, a suggestive QTL for backfat thickness
was detected with the best position at 26 cM. Imprinting analysis, however, revealed a genome-wise, significant, paternally
expressed QTL on SSC2 with the best position at 63 cM. Our results suggest that this QTL is different from the previously
reported paternally expressed QTL for muscle mass and fat deposition on the distal tip of SSC2p.
Received: 15 October 1999 / Accepted: 21 February 2000 相似文献
14.
Substitution mapping of Pup1: a major QTL increasing phosphorus uptake of rice from a phosphorus-deficient soil 总被引:2,自引:0,他引:2
Wissuwa M Wegner J Ae N Yano M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,105(6-7):890-897
A major QTL for P uptake had previously been mapped to a 13-cM marker interval on the long arm of chromosome 12. To map that major QTL with higher precision and certainty, a secondary mapping population was developed by backcrossing a near-isogenic line containing the QTL from the donor parent to the recurrent parent of low P uptake. Two different mapping strategies have been followed in this study. A conventional QTL mapping approach was based on individual F(2) RFLP data and the phenotypic evaluation of family means in the F(3). The second strategy employed a substitution-mapping approach. Phenotypic and marker data were obtained for 160 F(3) individuals of six highly informative families that differed in the size of donor chromosomal segments in the region of the putative QTL. QTL mapping showed that close to 80% of the variation between families was due to a single QTL, hereafter referred to as Pup1 (Phosphorus uptake 1). Pup1 was placed in a 3-cM interval flanked by markers S14025 and S13126, which is within 1 cM of the position identified in the original QTL mapping experiment. Other chromosomal regions and epistatic effects were not significant. Substitution mapping revealed that Pup1 co-segregated with marker S13126 and that the flanking markers, S14025 and S13752, were outside the interval containing Pup1. The two mapping strategies therefore yielded almost identical results and, in combining the advantages of both, Pup1 could be mapped with high certainty. The QTL mapping appoach showed that the phenotypic variation between families was due to only one QTL without any additional epistacic interactions, whereas the advantage of substitution mapping was to place clearly defined borders around the QTL. 相似文献
15.
Quantitative trait loci for urinary albumin in crosses between C57BL/6J and A/J inbred mice in the presence and absence of Apoe 下载免费PDF全文
Doorenbos C Tsaih SW Sheehan S Ishimori N Navis G Churchill G Dipetrillo K Korstanje R 《Genetics》2008,179(1):693-699
We investigated the effect of apolipoprotein E (Apoe) on albuminuria in the males of two independent F2 intercrosses between C57BL/6J and A/J mice, using wild-type inbred strains in the first cross and B6-Apoe(-/-) animals in the second cross. In the first cross, we identified three quantitative trait loci (QTL): chromosome (Chr) 2 [LOD 3.5, peak at 70 cM, confidence interval (C.I.) 28-88 cM]; Chr 9 (LOD 2.0, peak 5 cM, C.I. 5-25 cM); and Chr 19 (LOD 1.9, peak 49 cM, C.I. 23-54 cM). The Chr 2 and Chr 19 QTL were concordant with previously found QTL for renal damage in rat and human. The Chr 9 QTL was concordant with a locus found in rat. The second cross, testing only Apoe(-/-) progeny, did not identify any of these loci, but detected two other loci on Chr 4 (LOD 3.2, peak 54 cM, C.I. 29-73 cM) and Chr 6 (LOD 2.6, peak 33 cM, C.I. 11-61 cM), one of which was concordant with a QTL found in rat. The dependence of QTL detection on the presence of Apoe and the concordance of these QTL with rat and human kidney disease QTL suggest that Apoe plays a role in renal damage. 相似文献
16.
Nineteen markers for rat Chromosome 5 (Chr) were generated by screening chromosome-sorted DNA libraries and were subsequently
mapped by linkage to known markers by use of five F2 rat populations. Along with existing markers, these newly produced markers are potentially useful for fine mapping of certain
quantitative trait loci for blood pressure and for obesity.
Received: 20 January 1997 / Accepted: 17 March 1997 相似文献
17.
Quantitative trait loci for baseline erythroid traits 总被引:1,自引:0,他引:1
Luanne L. Peters Amy J. Lambert Weidong Zhang Gary A. Churchill Carlo Brugnara Orah S. Platt 《Mammalian genome》2006,17(4):298-309
A substantial genetic contribution underlies variation in baseline peripheral blood counts. We performed quantitative trait
locus/loci (QTL) analyses to identify chromosome (Chr) regions harboring genes influencing the baseline erythroid parameters
in F2 intercrosses between NZW/LacJ, SM/J, and C57BLKS/J inbred mice. We identified multiple significant QTL for red blood cell
(RBC) count, hemoglobin (Hgb) and hematocrit (Hct) levels, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH),
and mean cell hemoglobin concentration (CHCM). We identified four RBC count QTL: Rbcq1 (Chr 1, peak LOD score at 62 cM,), Rbcq2 (Chr 4, 60 cM), Rbcq3 (Chr 11, 34 cM), and Rbcq4 (Chr 10, 60 cM). Three MCV QTL were identified: Mcvq1 (Chr 7, 30 cM), Mvcq2 (Chr 11, 6 cM), and Mcvq3 (Chr 10, 60 cM). Single significant loci for Hgb (Hgbq1, Chr 16, 32 cM), Hct (Hctq1, Chr 3, 42 cM), and MCH (Mchq1, Chr 10, 60 cM) were identified. The data support the existence of a common RBC/MCH/MCV locus on Chr 10. Two QTL for CHCM
(Chcmq1, Chr 2, 48 cM; Chcmq2, Chr 9, 44 cM) and an interaction between Chcmq2 with a locus on Chr 19 were identified. These analyses emphasize the genetic complexity underlying the regulation of erythroid
peripheral blood traits in normal populations and suggest that genes not previously recognized as significantly impacting
normal erythropoiesis exist. 相似文献
18.
DNA marker analysis of loci conferring resistance to peanut root-knot nematode in soybean 总被引:4,自引:0,他引:4
J. P. Tamulonis B. M. Luzzi R. S. Hussey W. A. Parrott H. R. Boerma 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):664-670
Peanut root-knot nematode [Meloidogyne arenaria (Neal) Chitwood] (Ma) is a serious pathogen of soybean, Glycine max L. Merrill, in the southern USA. Breeding for root-knot nematode resistance is an important objective in many plant breeding
programs. The inheritance of soybean resistance to Ma is quantitative and has a moderate-to-high variance-component heritability
on a family mean basis. The objectives of the present study were to use restriction fragment length polymorphism (RFLP) markers
to identify quantitative trait loci (QTLs) conferring resistance to Ma and to determine the genomic location and the relative
contribution to resistance of each QTL. An F2 population from a cross between PI200538 (Ma resistant) and ‘CNS’ (Ma susceptible) was mapped with 130 RFLPs. The 130 markers
converged on 20 linkage groups spanning a total of 1766 cM. One hundred and five F2:3 families were grown in the greenhouse and inoculated with Ma Race 2. Two QTLs conferring resistance to Ma were identified
and PI200538 contributed the alleles for resistance at both QTLs. One QTL was mapped at 0-cM recombination with marker B212V-1
on linkage group-F (LG-F) of the USDA/ARS-Iowa State University RFLP map, and accounted for 32% of the variation in gall number.
Another QTL was mapped in the interval from B212D-2 to A111H-2 on LG-E, and accounted for 16% of the variation in gall number.
Gene action for the QTL located on LG-F was additive to partially dominant, whereas the gene action for the QTL on LG-E was
dominant with respect to resistance. The two QTLs, when fixed on the framework map, accounted for 51% of the variation in
gall number in a two-QTL model. The two QTLs for Ma resistance were found in duplicated regions of the soybean genome, and
the major QTL for Ma resistance on LG-F is positioned within a cluster of eight diverse disease-resistance loci.
Received: 10 June 1996 / Accepted: 18 April 1997 相似文献
19.
Although the phenomenon of innate resistance to flaviviruses in mice was recognized many years ago, it was only recently that the genetic locus (Flv) controlling this resistance was mapped to mouse Chromosome (Chr) 5. Here we report the fine mapping of the Flv locus, using 12 microsatellite markers which have recently been developed for mouse Chr 5. The new markers were genotyped in 325 backcross mice of both (C3H/HeJxC3H/ RV)F1xC3H/HeJ and (BALB/cxC3H/RV)F1xBALB/c backgrounds, relative to Flv. The composite genetic map that has been constructed identifies three novel microsatellite loci, D5Mit68, D5Mit159, and D5Mit242, tightly linked to the Flv locus. One of those loci, D5Mit159, showed no recombinations with Flv in any of the backcross mice analyzed, indicating tight linkage (<0.3 cM). The other two, D5Mit68 and D5Mit242, exhibited two and one recombinations with Flv (0.6 and 0.3 cM) respectively, defining the proximal and distal boundaries of a 0.9-cM segment around this locus. The proximal flanking marker, D5Mit68, maps to a segment on mouse Chr 5 homologous to human Chr 4. This, together with the previous data produced by our group, locates Flv to a region on mouse Chr 5 carrying segments that are conserved on either human Chr 4, 12, or 7, but present knowledge does not allow precise identification of the syntenic element. 相似文献
20.
Use of locus-specific AFLP markers to construct a high-density molecular map in barley 总被引:33,自引:5,他引:28
X. Qi P. Stam P. Lindhout 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(3-4):376-384
By using 25 primer combinations, 563 AFLP markers segregating in a recombinant inbred population (103 lines, F9) derived from L94/Vada were generated. The 38 AFLP markers in common to the existing AFLP/RFLP combined Proctor/Nudinka map,
one STS marker, and four phenotypic markers with known map positions, were used to assign present AFLP linkage groups to barley
chromosomes. The constructed high-density molecular map contains 561 AFLP markers, three morphological markers, one disease
resistance gene and one STS marker, and covers a 1062-cM genetic distance, corresponding to an average of one marker per 1.9
cM. However, extremely uneven distributions of AFLP markers and strong clustering of markers around the centromere were identified
in the present AFLP map. Around the centromeric region, 289 markers cover a genetic distance of 155 cM, corresponding to one
marker per 0.5 cM; on the distal parts, 906 cM were covered by 277 markers, corresponding to one marker per 3.3 cM. Three
gaps larger than 20 cM still exist on chromosomes 1, 3 and 5. A skeletal map with a uniform distribution of markers can be
extracted from the high-density map, and can be applied to detect and map loci underlying quantitative traits. However, the
application of this map is restricted to barley species since hardly any marker in common to a closely related Triticum species could be identified.
Received: 16 June 1997 / Accepted: 9 October 1997 相似文献