栽培稻F1花粉不育基因座S—a的分子定位

以栽培稻品种台中６５及其等基因Ｆ１不育系ＴＩＳＬ４为材料,用ＲＦＬＰ和ＲＡＰＤ等技术,对Ｆ１花粉不育基因座Ｓ－ａ定位。通过用ＲＦＬＰ和ＲＡＰＤ方法对亲本间进行多态性分析,发现亲本间的多态性很低,说明经多代回交后,在等基因系基因组中供体亲本的ＤＮＡ片段所占的比例很小。通过连锁分析,将Ｓ－ａ定位在第１染色体。Ｓ－ａ与分子标记ＣＤＯ５４８、Ｏ１１－１０００、ＲＧ１４６和Ｙ１３－５００之间的遗传距离分别为     

栽培稻与普遍野生稻两个重要分类性状花药长度和柱头外露率的QTL分析

用江西东乡普通野生稻（简称东乡普野）和桂朝２号的１１５株的ＢＣ１群体,构成了１张长度为１４１８．２ｃＭ．包含１２０个ＲＦＬＰ标记的遗传图谱,该图谱除第１染色体短臂上的标记的顺序与日本水稻基因组计划发表的图谱不同外,其他染色体上相对应的标记的顺序及标记之间的遗传距离基本一致。对控制花药长度和柱头外露率这两个栽培稻和野生稻的重要分类性状的ＱＴＬ分析结果表明,控制花药长度的２个ＱＴＬｓ分别位于第２染色体Ｃ４２４～Ｇ３９和第９染色体Ｃ２８０７～Ｃ１２６３间;控制柱头外露率的２个ＱＴＬｓ分别位于第５染色体Ｒ２２８９～Ｒ１５５３间和第８染色体Ｇ１１４９～Ｒ１９６３间。这两个重要分类性状的ＱＴＬｓ定位,为进一步研究野生稻进化到栽培稻的分子进化机理提供了有益的信息。     

利用生化及分子标记确定长穗偃麦草(Elytrigia elongatum, EE. 2n=14)染色体与小麦染色体的部分同源性

利用限制性片段长度多态性（ＲＦＬＰ）及等电聚焦（ＩＥＦ）技术确定普通小麦中国春－二倍体长穗僵麦草７个异附加系所附加的外源染色体与小麦染色体的部分同源性,共有８个生化标记,１３个ＲＦＬＰ标记在亲本间揭示了多态性。结果表明：长穗堰麦草的ＩＥ、２Ｅ、３Ｅ、４Ｅ、 ５Ｅ、６Ｅ、７Ｅ ７条染色体分别与小麦染色体的 １、２、３、４、５、６、７ ７个部分同源群具有部分同源关系,堰麦草的ＩＥ与７Ｅ、５Ｅ与７Ｅ染色体间可能发生过重排。同时,研究还分别将Ｅｓｔ－Ｅ５、Ｅｓｔ－Ｅ８位点定位于３ＥＬ,Ｐｅｒ－Ｅ１定位于７Ｅ, Ｐｅｒ－Ｅ４定位于５Ｅ,β－Ａｍｙ－Ｅ１定位于４ＥＬ染色体,并进一步将α－Ａｍｙ－Ｅ１位点定位于６Ｅ染色体长臂上。     

普通小麦4A染色体重排的原位杂交研究

以普通小麦第四部分同源染色体组的１３个ＲＦＬＰ（限制性片段长度多态性）标记为探针,通过原位杂交进行了物理定位和４Ａ染色体重排的物理特征研究。ＲＦＬＰ分析确定的标记所在的染色体臂和原位杂交结果相一致。位于４ＡＬ上的９个ＲＦＬＰ探针有６个的杂交点集中分布在距着丝点约６０％～７０％的区域内。本结果支持了４Ａ染色体来自于双重易位的假说,第一次易位产生的４ＡＬ／５ＡＬ染色体又和７ＢＳ发生易位,现在的４Ａ染色体结构为４ＡＬ／５ＡＬ／７ＢＳ,保留在４Ａ的５ＡＬ、７ＢＳ染色体片段约分别为０５μｍ、２２μｍ。所用ＲＦＬＰ标记杂交点聚集的区段分布于染色体臂的近端部,可能和易位断点及染色体的交换重组有关。４ＡＬ上Ｃ－带距着丝点的相对距离和各标记杂交点集中区段距着丝点的相对距离接近。     

微卫星DNA和AFLP标记在水稻分子标记连锁图上的分布

以一个栽培稻（ＯｒｙｚａｓａｔｉｖａＬ．ｓｐ．ｉｎｄｉｃａ）和野生稻（Ｏ．ｒｕｆｉｐｏｇｏｎＧｒｉｆ）杂交的Ｆ２作图群体以及由该群体构建的ＲＦＬＰ标记连锁图,分析了微卫星ＤＮＡ和ＡＦＬＰ标记的多态性、遗传行为及其在染色体上的分布。共定位了２８个微卫星ＤＮＡ标记和１７２个ＡＦＬＰ标记。２８个微卫星ＤＮＡ标记中有６个为华中农业大学作物遗传改良国家重点实验室根据数据库中序列而设计,其余２２个来自美国Ｃｏｒｎｅｌ大学已发表的结果。１７２个ＡＦＬＰ标记出自２５对引物扩增得到的２２８个多态性带的片段。这些标记分布于水稻的１２条染色体。将此２００个ＰＣＲ标记与华中农业大学作物遗传改良国家重点实验室构建的ＲＦＬＰ连锁图整合,得到一张含６１２个分子标记位点的遗传连锁图。     

利用生化及分子标记确定长穗偃麦草（Elytrigia elongatum,EE.2n=14） …

利用限制性片段长度多态性（ＲＦＬＰ）及等电聚焦（ＩＥＦ）技术确定普通小麦中国春－二倍体长穗偃麦草７个异附加系所附加的外源染以体与小麦染色体的部分同源性,共有８个生化标记,１３个ＲＦＬＰ标记在亲本间揭示了多态性,结果表明：长穗偃麦草的１Ｅ,２Ｅ,３Ｅ,４Ｅ,５Ｅ,６Ｅ,７Ｅ７条染色体分别与小麦染色体的１、２、３、４、５、６、７７个部分同源群具有部分同源关系,偃麦草的１Ｅ与７Ｅ、５Ｅ与７Ｅ染色体间可能     

利用分子标记定位农垦58S的光敏核不育基因

对农垦５８Ｓ（Ｏｒｙｚａｓａｔｉｖａｓｐ．ｊａｐｏｎｉｃａ）／大黑矮生标记基因系ＦＬ２组合组建可育集团和不育集团,并以亲本为对照进行了ＲＦＬＰ、ＲＡＰＤ和双引物ＲＡＰＤ分析,结果第１２染色体上的一个单拷贝标记Ｇ２１４０与光敏核不育基因连锁遗传,二者间的遗传图距为１４．１ｃＭ（ｃｅｎｔｉｍｏｒｇａｎ）。在筛选过的１０４０个随机单引物和１９０个双引物中,仅引物ＯＰＡＵ１０扩增出与光敏核不育基因连锁的１．５ｋｂＤＮＡ片段,回收、克隆该ＤＮＡ片段并制备探针,将其转换成共显性的ＲＦＬＰ标记并命名为ＯＰＡＵ１０１５００。分离群体连锁分析表明该标记与标记Ｇ２１４０紧密连锁,将农垦５８Ｓ的一对光敏核不育基因定位于第１２染色体上。     

基于三点测交的双标记 -QTL基因定位的相关方法

提出在测交群体中,对区间标记座位赋值后求其与待定位的数量性状表型值间的简单相关系数Ｒ,以此进行连锁测验,并且在一定条件下用Ｒ值求出该数量性状座位（ＱＴＬ）与各标记座位（ＭＬ）间的重组值。     

水稻对白叶枯病Xanthomonas oryzae pv.Oryzae水平抗性的数量性状 …

利用“Ｌｅｍｏｎｔ／特青”重组自交系（ＲＩ）群体研究了水稻对白叶枯病致病菌株ＣＲ６的水平抗性,双亲和Ｆ１均为感病,重组自交系（ＲＩＬｓ）的病斑长度（ＬＬ）为带有明显双向超亲的连续变异,显示出典型的多基因遗传特征,部分重组自交系（约占总数９０％）对ＣＲ６表现高水平抗性（ＬＬ≤３ｃｍ）利用由１７８个良好分离的ＲＦＬＰ标记构建的饱和连锁图。鉴定出１１个数量形状位点（ＱＴＬｓ）和３对互作位点解释了ＲＩ群体     

应用分子标记研究氮素胁迫条件下水稻叶片叶绿素含量差异的遗传背景

在氮素限制供应条件下,灿稻品种ＩＲ４２与广亲合粳稻品种Ｐａｌａｗａｎ剑叶及下位叶的平均叶绿素含量差异显著,叶绿素含量在Ｐａｌａｗａｎ／ＩＲ４２杂交Ｆ２代中呈正态分布,１０４个分布与１２条染色体的ＲＦＬＰ标记基因型之间表型平均值方差分析与区间作图分析结果表明,分别位于染色体２,４,７上的３个ＱＴＬ位于ＲＺ５８／ＲＧ１０２,ＲＧ１４３／ＲＧ３２９和ＲＧ６３４／ＲＧ６５０之间。与ＲＧ１４３及ＲＧ１０２连     

Linkage of Familial Schizophrenia to Chromosome 13q32

Over the past 4 years, a number of investigators have reported findings suggestive of linkage to schizophrenia, with markers on chromosomes 13q32 and 8p21, with one recent study by Blouin et al. reporting significant linkage to these regions. As part of an ongoing genome scan, we evaluated microsatellite markers spanning chromosomes 8 and 13, for linkage to schizophrenia, in 21 extended Canadian families. Families were analyzed under autosomal dominant and recessive models, with broad and narrow definitions of schizophrenia. All models produced positive LOD scores with markers on 13q, with higher scores under the recessive models. The maximum three-point LOD scores were obtained under the recessive-broad model: 3.92 at recombination fraction (theta).1 with D13S793, under homogeneity, and 4.42 with alpha=.65 and straight theta=0 with D13S793, under heterogeneity. Positive LOD scores were also obtained, under all models, for markers on 8p. Although a maximum two-point LOD score of 3.49 was obtained under the dominant-narrow model with D8S136 at straight theta=0.1, multipoint analysis with closely flanking markers reduced the maximum LOD score in this region to 2. 13. These results provide independent significant evidence of linkage of a schizophrenia-susceptibility locus to markers on 13q32 and support the presence of a second susceptibility locus on 8p21.     

直播条件下水稻6个穗部性状的QTL分析

在大田直播条件下,利用来源于＂Lemont/特青＂的重组自交系群体,对水稻6个穗部性状及其相互间遗传相关的分子基础进行了QTL分析,共检测到19个QTL,各性状QTL数为2～4个,单个QTL贡献率为4%～22%。共检测到3个染色体区段能同时影响多个穗部性状,其中第1染色体RM212-RM104和第2染色体RM263-RM221区段的QTL能同时影响单株产量、每穗颖花数、着粒密度和二次枝梗数中的3个或4个性状,且这2个区段的QTL对各性状的效应方向相同,增效等位基因均来自‘特青’,为各性状间表型正相关提供了重要的遗传解释。第11染色体RG1022附近的QTL对着粒密度的效应值为负,来自‘特青’的等位基因增加性状值,而对穗长的效应值为正,来自‘特青’的等位基因降低性状值,为这2个性状间表型负相关也提供了一定的遗传解释。此外,对水稻穗部性状QTL在多种环境和遗传背景下的稳定表达及其在分子标记辅助育种中的应用进行了讨论。     

Novel pleiotropic loci controlling panicle architecture across environments in japonica rice （Oryza sativa L.）

To identify quantitative trait loci (QTLs) controlling panicle architecture in japonica rice, a genetic map was constructed based on simple sequence repeat (SSR) markers and 254 recombinant inbred lines (RILs) derived from a cross between cultivars Xiushui 79 and C Bao. Seven panicle traits were investigated under three environments. Single marker analysis indicated that a total of 27 SSR markers were highly associated with panicle traits in all the three environments. Percentage of phenotypic variation explained by single locus varied from 2% to 35%. Based on the mixed linear model, a total of 40 additive QTLs for seven panicle traits were detected by composite interval mapping, explaining 1.2%-35% of phenotypic variation. Among the 9 QTLs with more than 10% of explained phenotypic variation, two QTLs were for the number of primary branches per panicle (NPB), two for panicle length (PL), two for spikelet density (SD), one for the number of secondary branches per panicle (NSB), one for secondary branch distribution density (SBD), and one for the number of spikelets per panicle (NS), respectively. qPLSD-9-1 and qPLSD-9-2 were novel pleiotropic loci, showing effects on PL and SD simultaneously. qPLSD-9-1 explained 34.7% of the phenotypic variation for PL and 25.4% of the phenotypic variation for SD, respec- tively. qPLSD-9-2 explained 34.9% and 24.4% of the phenotypic variation for PL and SD, respectively. The C Bao alleles at the both QTLs showed positive effects on PL, and the Xiushui 79 alleles at the both QTLs showed positive effects on SD. Genetic variation of panicle traits are mainly attributed to additive effects. QTL × environment interactions were not significant for additive QTLs and additive × additive QTL pairs.     

A genome scan for serum triglyceride in obese nuclear families

Serum triglyceride (TG) levels are increased in extremely obese individuals, indicating abnormalities in lipid metabolism and insulin resistance. We carried out a genome scan for serum TG in 320 nuclear families segregating extreme obesity and normal weight. Three hundred eighty-two Marshfield microsatellite markers (Screening Set 11) were genotyped. Quantitative linkage analyses were performed using family regression and variance components methods. We found linkage on the 7q36 region [D7S3058, 174 centimorgan (cM), Logarithm of Odds (LOD) = 2.98] for log-transformed TG. We also found suggestive linkages on chromosomes 20 (D20S164, 101 cM, LOD = 2.34), 13 (111 cM, LOD = 2.00), and 9 (104 cM, LOD = 1.90) as well as some weaker trends for chromosomes 1, 3, 5, 10, 12, and 22. In 58 African American families, LOD scores of 3.66 and 2.62 were observed on two loci on chromosome 16: D16S3369 (64 cM) and MFD466 (100 cM). To verify the 7q36 linkage, we added 60 nuclear families, and the LOD score increased to 3.52 (empirical P < 0.002) on marker D7S3058.     

QTL mapping and molecular marker analysis for the resistance of rice to ozone

The resistance of rice to ozone (O3) is a quantitative trait controlled by nuclear genes. The identification of quantitative trait loci (QTL) and analysis of molecular markers of O3 resistance is important for increasing the resistance of rice to O3 stress. QTL associated with the O3 resistance of rice were mapped on chromosomes 1, 7 and 11 using 164 recombinant inbred (RI) lines from a cross between 'Milyang 23' and 'Gihobyeo'. The quantitative trait loci were tightly linked to the markers RG109, C507 and RG1094 and were detected in each of three replications. The association between these markers and O3 resistance in 26 rice cultivars and doubled haploid (DH) populations was analysed. The markers permit the screening of rice germplasm for O3 resistance and the introduction of resistance into elite lines in breeding programs.     

Genome scan for loci involved in cleft lip with or without cleft palate,in Chinese multiplex families

Cleft lip with or without cleft palate (CL/P) is a common congenital anomaly. Birth prevalences range from 1/500 to 1/1,000 and are consistently higher in Asian populations than in populations of European descent. Therefore, it is of interest to determine whether the CL/P etiological factors in Asian populations differ from those in white populations. A sample of 36 multiplex families were ascertained through probands with CL/P who were from Shanghai. This is the first reported genome-scan study of CL/P in any Asian population. Genotyping of Weber Screening Set 9 (387 short tandem-repeat polymorphisms with average spacing approximately 9 cM [range 1-19 cM]) was performed by the Mammalian Genotyping Service of Marshfield Laboratory. Presented here are the results for the 366 autosomal markers. Linkage between each marker and CL/P was assessed by two-point and multipoint LOD scores, as well as with multipoint heterogeneity LOD scores (HLODs) plus model-free identity-by-descent statistics and the multipoint NPL statistic. In addition, association was assessed via the transmission/disequilibrium test. LOD-score and HLOD calculations were performed under a range of models of inheritance of CL/P. The following regions had positive multipoint results (HLOD > or =1.0 and/or NPL P< or =.05): chromosomes 1 (90-110 cM), 2 (220-250 cM), 3 (130-150 cM), 4 (140-170 cM), 6 (70-100 cM), 18 (110 cM), and 21 (30-50 cM). The most significant multipoint linkage results (HLOD > or =2.0; alpha=0.37) were for chromosomes 3q and 4q. Associations with P< or =.05 were found for loci on chromosomes 3, 5-7, 9, 11, 12, 16, 20, and 21. The most significant association result (P=.009) was found with D16S769 (51 cM).     

RFLP mapping of QTLs for yield and related characters in rice (Oryza sativa L.)

Quantitative triat loci (QTLs) for yield and related traits in rice were mapped based on RFLP maps from two indica/indica F₂ populations, Tesanai 2/CB and Waiyin 2/CB. In Tesanai 2/CB, 14 intervals carrying QTLs for eight traits were detected, including 3 for grain weight per plant (GWT), 2 for number of panicles per plant (NP), 2 for number of grains per panicle (NG), 1 for total number of spikelets per panicle (TNS), 1 for spikelet fertility (SF), 3 for 1000-grain weight (TGWT), 1 for spikelet density (SD), and 1 for number of first branches per main panicle. The 3 QTLs for GWT were located on chromosomes 1, 2, and 4, with 1 in each chromosome. The additive effect of the single locus ranged from 2.0 g to 9.1 g. A major gene (np4) for NP was detected on chromosome 4 within the interval of RG143–RG214, about 4cM for RG143, and this locus explained 26.1% of the observed phenotypic variance for NP. The paternal allele of this locus was responsible for reduced panicles per plant (3 panicles per plant). In another population, Waiyin 2/CB, 12 intervals containing QTLs for six of the above-mentioned traits were detected, including 3 for GWT, 2 for each of NP, TNS, TGWT and SD, 1 for SF. Three QTLs for GWT were located on chromosome 1, 4, and 5, respectively. The additive effect of the single locus for GWT ranged from 6.7 g to 8.8 g, while the dominance effect was 1.7–11.5 g. QTL mapping in two populations with a common male parent is compared and discussed.     

水稻糙米重金属Cd含量的QTL分析

镉(Cd²⁺)是一种分布较广泛、毒性较强的一种重金属, 文章利用韭菜青×IR26杂交衍生的一个重组自交系群体(Recombinant inbred lines, RIL)及构建的SSR分子遗传图谱, 对控制糙米中Cd²⁺含量的QTL进行分析, 为选育籽粒中Cd²⁺低吸收或低积累的水稻品种提供参考。结果表明, 在Cd²⁺胁迫(5 mg/kg)处理条件下, 共检测到2个与糙米Cd²⁺含量有关的QTLs, 分别位于水稻第11染色体上的标记RM6288-RM6544和RM167-RM5704之间, 其中qCCBR-11a对表型贡献率为11.17%, 加性效应0.089; qCCBR-11b对表型变异贡献率为7.66%, 加性效应0.075。相关分析显示, 糙米Cd²⁺含量与株高、每穗总粒数、每穗实粒数、结实率和千粒重等产量性状的相关性均不显著, 糙米中Cd²⁺含量是一个相对独立、由基因控制的遗传性状。     

云南元江普通野生稻穗颈维管束和穗部性状的QTL分析

以云南元江普通野生稻为供体亲本,籼稻品种特青为轮回亲本构建高代回交群体,用SSR标记构建连锁图谱,在第1、2、3、4、7和10染色体上定位到7个控制穗颈大维管束数的QTL,在第1、2、3、4和8染色体上定位到5个控制穗颈小维管束数的QTL,在第11和12以外的10条染色体上,共定位到15个控制穗一、二次枝梗数和穗颖花数QTL。来自野生稻的等位基因大多表现负效,能显著减少群体的穗颈维管束数、枝梗数和颖花数,说明从野生稻演化成栽培稻的过程中,可能淘汰了一些对产量不利的QTL,保留了有利的QTL。相当一部分控制穗颈维管束数、枝梗数及颖花数的QTL在染色体上成簇分布或紧密连锁,且加性效应的方向一致,从理论上解释了这些性状表型显著相关的遗传基础,同时也说明在人工选择或自然选择下,这些性状可能存在平行进化或协同进化的关系。