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1.
Integrated map of AFLP, SSLP and RFLP markers using a recombinant inbred population of rice (Oryza sativa L.) 总被引:7,自引:0,他引:7
Y. G. Cho S. R. McCouch M. Kuiper M.-R. Kang J. Pot J. T. M. Groenen M. Y. Eun 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(3):370-380
A molecular map of rice consisting of 231 amplified fragment length polymorphisms (AFLPs), 212 restriction fragment length
polymorphisms (RFLPs), 86 simple-sequence length polymorphisms (SSLPs), five isozyme loci, and two morphological mutant loci
[phenol staining of grain (Ph), semi-dwarf habit (sd-1)] has been constructed using an F11 recombinant inbred (RI) population. The mapping population consisted of 164 RI lines and was developed via single-seed descent
from an intercross between the genetically divergent parents Milyang 23 (M) (tongil type) and Gihobyeo (G) ( japonica type). A subset of previously mapped RFLP and SSLP markers were used to construct the map framework. The AFLP markers were
derived from ten EcoRI(+2) and MseI(+3) primer combinations. All marker types were well distributed throughout the 12 chromosomes. The integrated map covered
1814 cM, with an average interval size of 3.4 cM. The MG map is a cornerstone of the Korean Rice Genome Research Program (KRGRP)
and is being continuously refined through the addition of partially sequenced cDNA markers derived from an immature-seed cDNA
library developed in Korea, and microsatellite markers developed at Cornell. The population is also being used for quantitative
trait locus (QTL) analysis and as the basis for marker-assisted variety development.
Received: 24 June 1997 / Accepted: 25 November 1997 相似文献
2.
S. Fukuoka H. Namai K. Okuno 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(3):446-449
Complementary recessive genes hwd1 and hwd2 controlling hybrid breakdown (weakness of F2 and later generations) were mapped in rice using RFLP markers. These genes produce a plant that is shorter and has fewer
tillers than normal plants when the two loci have only one or no dominant allele at both loci. A cultivar with two dominant
alleles at the hwd1 locus and a cultivar with two dominant alleles at the hwd2 locus were crossed with a double recessive tester line. Linkage analysis was carried out for each gene independently in two
F2 populations derived from these crosses. hwd1 was mapped on the distal region of rice genetic linkage map for chromosome 10, flanked by RFLP markers C701 and R2309 at
a distance of 0.9 centiMorgans (cM) and 0.6 cM, respectively. hwd2 was mapped in the central region of rice genetic linkage map for chromosome 7, tightly linked with 4 RFLP markers without
detectable recombination. The usefulness of RFLP mapping and map information for the genes controlling reproductive barriers
are discussed in the context of breeding using diverse rice germplasm, especially gene introduction by marker-aided selection. 相似文献
3.
普遍野生稻和亚洲栽培稻遗传多样性的研究 总被引:2,自引:0,他引:2
用 44个 RFLP标记对来自中国、印度、泰国等亚洲 10个国家的普通野生稻(简称普野,下同)和来自多个国家的75个栽培稻品种,从多态位点的比率、等位基因数、基因型数、平均杂合度及平均基因多样性等多个方面,比较了不同国家和不同地区的普通野生稻、栽培稻籼粳亚种及栽培稻与普野之间遗传多样性的差异。结果表明:中国普野的遗传多样性最大;其次是印度普野;南亚普野的平均基因多样性大于东南亚普野,而多态位点的比率、等位基因数及基因型数等却低于东南亚普野;栽培稻的遗传多样性明显小于普通野生稻。在所检测的44个位点中,栽培稻的多态位点数仅为野生稻的3/4,等位基因数约为野生稻的60%,基因型种类约为野生稻的1/2。栽培稻中籼稻的遗传多样性高于粳稻。在平均每个位点的实际杂合度上,以中国普野杂合度最高,普通野生稻是栽培稻的2倍。说明从野生稻演化成栽培稻的过程中,经过自然选择和人工选择,杂合度降低,等位基因减少,基因多样性下降。 相似文献
4.
V. T. Nguyen M. D. Burow H. T. Nguyen B. T. Le T. D. Le A. H. Paterson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(6-7):1002-1010
Crop productivity on acid soil is restricted by multiple abiotic stress factors. Aluminum (Al) tolerance seems to be a key
to productivity on soil with a pH below 5.0, but other factors such as Mn toxicity and the deficiency of P, Ca and Mg also
play a role. The development of Al-tolerant genotypes of rice is an urgent necessity for improving crop productivity in developing
countries. Inhibition of root growth is a primary and early symptom of Al toxicity. The present study was conducted to identify
genetic factors controlling the aluminum tolerance of rice. Several parameters related to Al tolerance, most importantly the
relative root growth under Al stress versus non-stress conditions, were scored in 188 F3 selfed families from a cross between an Al-tolerant Vietnamese local variety, Chiembau, and an Al-susceptible improved variety,
Omon269–65. The two varieties are both Oryza sativa ssp. indica, but showed a relatively high level of DNA polymorphism, permitting the assembly of an RFLP map consisting of
164 loci spanning 1,715.8 cM, and covering most of the rice genome. A total of nine different genomic regions on eight chromosomes
have been implicated in the genetic control of root and shoot growth under aluminum stress. By far the greatest effects on
aluminum tolerance were associated with the region near WG110 on chromosome 1. This region does not seem to correspond to
most of the genes that have been mapped for aluminum tolerance in other species, nor do they correspond closely to one another.
Most results, both from physiological studies and from molecular mapping studies, tend to suggest that aluminum tolerance
is a complex multi-genic trait. The identification of DNA markers (such as WG110) that are diagnostic for aluminum tolerance
in particular gene pools provides an important starting point for transferring and pyramiding genes that may contribute to
the sustainable improvement of crop productivity in aluminum-rich soils. The isolation of genes responsible for aluminum tolerance
is likely to be necessary to gain a comprehensive understanding of this complex trait.
Received: 29 March 2000 / Accepted: 16 August 2000 相似文献
5.
L.-z. Gao S. G. De-y. Hong 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(3):494-502
In order to determine the genetic diversity and genetic structure of populations in common wild rice Oryza rufipogon, an endangered species, allozyme diversity was analyzed using 22 loci in 607 individuals of 21 natural populations from the
Guangxi, Guangdong, Hainan, Yunnan, Hunan, Jiangxi and Fujian provinces in China. The populations studied showed a moderate
allozyme variability (A=1.33, P=22.7%, Ho=0.033 and He=0.068), which was relatively high for the genus Oryza. The levels of genetic diversity for Guangxi and Guangdong were significantly higher than those for the other regions, and
thus South China appeared to be the center of genetic diversity of O. rufipogon in China. A moderate genetic differentiation (FST=0.310, I=0.964) was found among the populations studied. Interestingly, the pattern of population differentiation does not
correspond to geographic distance. An estimate of the outcrossing rate (t=0.324) suggests that the species has a typical mixed-mating
system. The deficit of heterozygotes (F=0.511) indicates that some inbreeding may have taken place in outcrossing asexual
populations because of intra-clone outcrossing events and ”isolation by distance” as a result of human disturbance. In order
to predict the long-term genetic survival of fragmented populations, further studies on gene flow among the remaining populations
and the genetic effects of fragmentation are proposed. Finally, some implications for the conservation of endangered species
are suggested.
Received: 22 June 1999 / Accepted: 20 December 1999 相似文献
6.
R. H. Li C. G. Xue L. P. Yuan Y. Q. He C. Q. Sun S. B. Yu X. H. Li X. K. Wang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(3-4):526-538
This study was intended to investigate the extent of genetic differentiation in parental lines of rice hybrids and to analyze
the genetic basis underlying the fertility phenomenon in distant crosses. Two subsets of rice material (111 entries in total)
were used, including 81 doubled-haploid (DH) lines and 30 Indica and Japonica rice varieties or lines (as a control). The
DH lines was derived from a heterotic Indica/Japonica cross (Gui630/02428) by anther culture. The materials in the control
represent a broad spectrum of the Asian cultivated rice gene pool including landraces, primitive cultivars, historically important
cultivars, modern elite cultivars, super rice and parents of superior hybrids. In accordance with the NC II design, 57 out
of the DH lines were test-crossed to two important wide compatibility lines: photoperiod-sensitive genetic male sterile (PGMS)
line N422s and thermo-sensitive genetic male sterile (TGMS) line Peiai64s. The F1s and their parents, 182 entries in total, were examined for the performance of seven traits in a replicated field trial.
All the rice materials was surveyed for polymorphisms using 92 RFLP markers selected from two published molecular marker linkage
maps. Genotypes of the F1 hybrids at the molecular-marker loci were deduced from the parental genotypes. The analysis showed that there were two types
of genetic differentiation in the two subsets of rice material; that is, qualitative differentiation in the control and quantitative
differentiation in the DH lines. In addition, favorable genic interactions (both intra- or inter-locus) contributed to better
increase the fertility in hybrids of distant crosses through incorporation of a wide-compatibility line as the female parent.
Favorable genic interactions can be applied in hybrid rice breeding programs by selecting parents with an appropriate extent
of genetic differentiation.
Received: 5 June 1997 / Accepted: 10 September 1997 相似文献
7.
S. Garland L. Lewin A. Blakeney R. Reinke R. Henry 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(3):364-371
The genomic DNA clone RG28, linked to the major fragrance gene of rice (fgr), was assessed for polymorphism in order to produce a PCR-based marker for fragrance. A small mono-nucleotide repeat, that
was polymorphic between a pair of fragrant and non-fragrant cultivars, was identified and developed into a co-dominant PCR-based
marker. The polymorphism-information-content determinations for three microsatellite markers, that have been genetically mapped
near RG28, are also presented. These PCR-based markers will be highly useful in distinguishing fragrance-producing alleles
from non-fragrance-producing alleles at the fgr locus.
Received: 19 October 1999 / Accepted: 16 December 1999 相似文献
8.
Mapping and genome organization of microsatellite sequences in rice (Oryza sativa L.) 总被引:23,自引:15,他引:23
S. Temnykh William D. Park Nicola Ayres Sam Cartinhour N. Hauck L. Lipovich Y. G. Cho T. Ishii S. R. McCouch 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(5):697-712
In order to enhance the resolution of an existing genetic map of rice, and to obtain a comprehensive picture of marker utility
and genomic distribution of microsatellites in this important grain species, rice DNA sequences containing simple sequence
repeats (SSRs) were extracted from several small-insert genomic libraries and from the database. One hundred and eighty eight
new microsatellite markers were developed and evaluated for allelic diversity. The new simple sequence length polymorphisms
(SSLPs) were incorporated into the existing map previously containing 124 SSR loci. The 312 microsatellite markers reported
here provide whole-genome coverage with an average density of one SSLP per 6 cM. In this study, 26 SSLP markers were identified
in published sequences of known genes, 65 were developed based on partial cDNA sequences available in GenBank, and 97 were
isolated from genomic libraries. Microsatellite markers with different SSR motifs are relatively uniformly distributed along
rice chromosomes regardless of whether they were derived from genomic clones or cDNA sequences. However, the distribution
of polymorphism detected by these markers varies between different regions of the genome.
Received: 5 May 1999 / Accepted: 16 August 1999 相似文献
9.
J. P. Gustafson M. Yano 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(3-4):447-453
Minisatellites, or DNA fingerprinting sequences, have been utilized in animal linkage studies for several years but have not
been used as markers for plant genome mapping. In animal genome mapping they have resulted in limited success because they
are evenly dispersed in some species but are often clustered near telomeric regions, as observed on human chromosomes. The
purpose of the present study was to generate DNA fingerprints utilizing several rice-derived minisatellites containing different
core sequences and numbers of repeat units, followed by assessing their potential for use as genetic markers when mapped to
a rice recombinant inbred line (RIL) population. Sites of segregating minisatellite loci were mapped onto 11 of the 12 rice
RIL linkage maps. The implications for the use of rice minisatellite core sequences as genetic markers on linkage maps in
rice are discussed.
Received: 1 March 1999 / Accepted: 22 June 1999 相似文献
10.
Characterization and genetic mapping of a short, highly repeated, interspersed DNA sequence from rice (Oryza sativa L.). 总被引:8,自引:0,他引:8
Summary A short, highly repeated, interspersed DNA sequence from rice was characterized using a combination of techniques and genetically mapped to rice chromosomes by restriction fragment length polymorphism (RFLP) analysis. A consensus sequence (GGC)n, where n varies from 13–16, for the repeated sequence family was deduced from sequence analysis. Southern blot analysis, restriction mapping of repeat element-containing genomic clones, and DNA sequence analysis indicated that the repeated sequence is interspersed in the rice genome, and is heterogeneous and divergent. About 200000 copies are present in the rice genome. Single copy sequences flanking the repeat element were used as RFLP markers to map individual repeat elements. Eleven such repeat elements were mapped to seven different chromosomes. The strategy for characterization of highly dispersed repeated DNA and its uses in genetic mapping, DNA fingerprinting, and evolutionary studies are discussed. 相似文献
11.
Development of a microsatellite framework map providing genome-wide coverage in rice (Oryza sativa L.) 总被引:49,自引:0,他引:49
X. Chen S. Temnykh Y. Xu Y. G. Cho S. R. McCouch 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(4):553-567
Ninety-four newly developed microsatellite markers were integrated into existing RFLP framework maps of four rice populations,
including two doubled haploid, a recombinant inbred, and an interspecific backcross population. These simple sequence repeats
(SSR) were predominantly poly(GA) motifs, targetted because of their abundance in rice. They were isolated from a previously
described sheared library and a newly constructed enzyme-digested library. Differences in the average length of poly(GA) tracts
were observed for clones isolated from the two libraries. The length of GA motifs averaged 21 repeat units for clones isolated
from the Tsp-509-digested library, while motifs averaged 17 units for clones from the sheared library. There was no evidence of clustering
of microsatellite markers near centromeres or telomeres. Mapping of the 94 newly developed markers as well as of 27 previously
reported microsatellites provided genome-wide coverage of the 12 chromosomes, with an average distance of 1 SSLP (simple sequence
repeat polymorphism) per 16–20 cM.
Received: 13 February 1997/Accepted: 28 February 1997 相似文献
12.
K. K. Jena G. Kochert G. S. Khush 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1992,84(5-6):608-616
Summary Fifty-two introgression lines (BC2F8) from crosses between two Oryza sativa parents and five accessions of O. officinalis were analyzed for the introgression of O. officinalis chromosome segments. DNA from the parents and introgression lines was analyzed with 177 RFLP markers located at approximately 10-cM intervals over the rice chromosomes. Most probe/enzyme combinations detected RFLPs between the parents. Of the 174 informative markers, 28 identified putative O. officinalis introgressed chromosome segments in 1 or more of the introgression lines. Introgressed segments were found on 11 of the 12 rice chromosomes. In most cases of introgression, O. sativa RFLP alleles were replaced by O. officinalis alleles. Introgressed segments were very small in size and similar in plants derived from early and later generations. Some nonconventional recombination mechanism may be involved in the transfer of such small chromosomal segments from O. officinalis chromosomes to those of O. sativa. Some of the introgressed segments show association with genes for brown planthopper (BPH) resistance in some introgressed lines, but not in others. Thus, none of the RFLP markers could be unambiguously associated with BPH resistance. 相似文献
13.
Evaluation of the extent of genetic variability among Theobroma cacao accessions using RAPD and RFLP markers 总被引:1,自引:0,他引:1
E. Lerceteau T. Robert V. Pétiard D. Crouzillat 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(1-2):10-19
Random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) markers were used to evaluate
genetic relationships within the Theobroma cacao species and to assess the organization of its genetic diversity. Genetic variability was estimated with 18 primers and 43
RFLP probes on 155 cocoa trees belonging to different morphological groups and coming from various geographic origins. The
majority of the RFLP probes issued from low-copy DNA sequences. On the basis of on the genetic distance matrices, the two
molecular methods gave related estimates of the genetic relationship between genotypes. Although an influence of cocoa morphological
groups and geographical origins of trees was observed, a lack of gene differentiation characterized the T. cacao accessions studied. The continuous RFLP variability observed within the species may reflect the hybridization and introgressions
between trees of different origins. Nevertheless, the Nacional type was detected to be genetically specific and different
from well-known types such as Forastero, Criollo and Trinitario. Some of those genotypes were characterized by a low heterozygosity
rate and may constitute the original Nacional pool. These results also provide information for the constitution of a cocoa
tree core collection.
Received: 10 June 1996/Accepted: 11 October 1996 相似文献
14.
C. Y. Liao P. Wu B. Hu K. K. Yi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(1):104-111
A double-haploid (DH) population and a recombinant inbred (RI) line population, derived from a cross between a tropical japonica variety, Azucena, as male parent and two indica varieties, IR64 and IR1552, as female parents respectively, were used in both field and pot experiments for detecting QTLs
and epistasis for rice panicle number in different genetic backgrounds and different environments. Panicle number (PN) was
measured at maturity. A molecular map with 192 RFLP markers for the DH population and a molecular map with 104 AFLP markers
and 103 RFLP markers for the RI population were constructed, in which 70 RFLP markers were the same. Six QTLs were identified
in the DH population, including two detected from field experiments and four from pot experiments. The two QTLs, mapped on
chromosomes 1 and 12, were identical in both field and pot experiments. In the RI population, nine QTLs were detected, five
QTLs from field conditions and four from the pot experiments. Three of these QTLs were identical in both experimental conditions.
Only one QTL, linked to CDO344 on chromosome 12, was detected across the populations and experiments. Different epistasitic
interaction loci on PN were found under different populations and in different experimental conditions. One locus, flanked
by RG323 and RZ801 on chromosome 1, had an additive effect in the DH population, but epistatic effects in the RI population.
These results indicate that the effect of genetic background on QTLs is greater than that of environments, and epistasis is
more sensitive to genetic background and environments than main-effect QTLs. QTL and epistatic loci could be interchangeable
depending on the genetic backgrounds and probably on the environments where they are identified.
Received: 26 May 2000 / Accepted: 19 October 2000 相似文献
15.
16.
Construction of an RFLP linkage map for cultivated sunflower 总被引:5,自引:0,他引:5
C. C. Jan B. A. Vick J. F. Miller A. L. Kahler E. T. Butler III. 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,96(1):15-22
An RFLP linkage map was constructed for cultivated sunflower Helianthus annuus L., based on 271 loci detected by 232 cDNA probes. Ninety-three F2 plants of a cross between inbred lines RHA 271 and HA 234 were used as the mapping population. These genetic markers plus
a fertility restoration gene, Rf
1, defined 20 linkage groups, covering 1164 cM of the sunflower genome. Of the 71 loci 202 had codominant genotypic segregation,
with the rest showing dominant segregation. Thirty-two of the 232 probes gave multiple locus segregation. There were 39 clusters
of tightly linked markers with 0 cM distance among loci. This map has an average marker-to-marker distance of 4.6 cM, with
11 markerless regions exceeding 20 cM.
Received: 17 June 1997 / Accepted: 19 June 1997 相似文献
17.
Gao LZ Schaal BA Zhang CH Jia JZ Dong YS 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,106(1):173-180
The genetic structure of five natural populations of common wild rice Oryza rufipogon Griff. from China, was investigated with 21 microsatellite loci and compared to estimates of genetic diversity and genetic differentiation detected by 22 allozyme loci. Microsatellite loci, as expected, have much higher levels of genetic diversity (mean values of A = 3.1, P = 73.3%, Ho = 0.358 and He = 0.345) than allozyme loci (mean values of A = 1.2, P = 12.7%, Ho = 0.020 and He = 0.030). Genetic differentiation detected by microsatellite loci ( FST = 0.468, mean I = 0.472) was higher than that for allozyme loci ( FST =0.388, mean I = 0.976). However, microsatellite markers showed less deviation from Hardy-Weinberg expectation (Wright's inbreeding coefficient FIS = -0.069) than do allozymes ( FIS = 0.337). These results suggest that microsatellite markers are powerful high-resolution tools for the accurate assessment of important parameters in population biology and conservation genetics of O. rufipogon, and offer advantages over allozyme markers. 相似文献
18.
Q. Zhang K. D. Liu G. P. Yang M. A. Saghai Maroof C. G. Xu Z. Q. Zhou 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(1-2):112-118
The partial sterility of hybrids between the indica and japonica rice subspecies of Asian cultivated rice is a serious constraint
for utilizing inter-subspecific heterosis in hybrid rice breeding. In this study, we have investigated the relationship between
molecular-marker polymorphism and indica-japonica hybrid fertility using a diallel set involving 20 rice accessions including
9 indica and 11 japonica varieties. Spikelet fertility of the resulting 190 F1s and their parents was examined in a replicated field trial. Intra-subspecific hybrids showed much higher spikelet fertility
than inter-subspecific hybrids except in crosses involving wide-compatibility varieties. The parents were surveyed for DNA
polymorphism using 96 RFLP and ten SSR markers, which revealed extensive genetic differentiation between indica and japonica
varieties. A large number of markers detected highly significant effects on hybrid fertility. The chromosomal locations for
many of the positive markers coincided well with previously identified loci for hybrid sterility. The correlation between
hybrid fertility and parental distance was low in both intra- and inter-subspecific crosses. The results suggest that the
genetic basis of indica-japonica hybrid sterility is complex. It is the qualitative, rather than the quantitative, difference
between the parents that determines the fertility of hybrids.
Received: 3 January 1997/Accepted: 17 January 1997 相似文献
19.
Identification of a set of RFLP probes for subspecies differentiation in Oryza sativa L. 总被引:2,自引:0,他引:2
H-R. Qian J-Y. Zhuang H-X. Lin J. Lu K-L. Zheng 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(6):878-884
Sixty-eight indica-japonica tester-differentiating RFLP probes were tested in seven indica and seven japonica varieties of rice (Oryza sativa L.) with four enzyme digestions (EcoRI, EcoRV, HindIII and DraI). Twenty-one DNA clones were isolated as indica-japonica subspecies-differentiating probes. A set of 13 probes was established as core probes for subspecies differentiation and a pooled blotting analysis was carried out to facilitate the application of RFLP in rice genetics and breeding practice. A dendrogram of 12 wide-compatibility varieties was constructed based on RFLPs detected by 13 core probes with single enzyme digestions. It was speculated that most RFLPs of indica-japonica differentiating probes were generated by insertions/deletions, which may be of great significance for the origin and differentiation of subspecies in Oryza sativa L. 相似文献
20.
Diversity of microsatellites derived from genomic libraries and GenBank sequences in rice (Oryza sativa L.) 总被引:14,自引:14,他引:14
Y. G. Cho T. Ishii S. Temnykh X. Chen L. Lipovich S. R. McCouch W. D. Park N. Ayres S. Cartinhour 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(5):713-722
The growing number of rice microsatellite markers warrants a comprehensive comparison of allelic variability between the markers
developed using different methods, with various sequence repeat motifs, and from coding and non-coding portions of the genome.
We have performed such a comparison over a set of 323 microsatellite markers; 194 were derived from genomic library screening
and 129 were derived from the analysis of rice-expressed sequence tags (ESTs) available in public DNA databases. We have evaluated
the frequency of polymorphism between parental pairs of six inter- subspecific crosses and one inter-specific cross widely
used for mapping in rice. Microsatellites derived from genomic libraries detected a higher level of polymorphism than those
derived from ESTs contained in the GenBank database (83.8% versus 54.0%). Similarly, the other measures of genetic variability
[the number of alleles per locus, polymorphism information content (PIC), and allele size ranges] were all higher in genomic
library-derived microsatellites than in their EST-database counterparts. The highest overall degree of genetic diversity was
seen in GA-containing microsatellites of genomic library origin, while the most conserved markers contained CCG- or CAG-trinucleotide
motifs and were developed from GenBank sequences. Preferential location of specific motifs in coding versus non-coding regions
of known genes was related to observed levels of microsatellite diversity. A strong positive correlation was observed between
the maximum length of a microsatellite motif and the standard deviation of the molecular-weight of amplified fragments. The
reliability of molecular weight standard deviation (SDmw) as an indicator of genetic variability of microsatellite loci is
discussed.
Received: 5 May 1999 / Accepted: 16 August 1999 相似文献