南德温杂交肉牛生长分化因子10基因多态性与体尺性状的关联分析

以98头南德温杂交肉牛血样为材料,随机抽样构建混合DNA池,利用高分辨率熔解曲线分析技术和直接测序法检测生长分化因子10(growth differentiation factor 10,GDF10)基因的序列变异,研究分析GDF10基因的多态性.采用SHEsis和PHASE软件对GDF10基因多态位点进行配对连锁不平衡和单倍型分析,采用SPSS 17.0进行基因多态位点和单倍型组合与体尺性状关联性分析.结果显示,南德温杂交肉牛GDF10基因检测到3个多态位点1113(G/A)、9569(G/A)和9628(G/A);关联分析表明,南德温杂交肉牛GDF10基因不同突变位点的基因型与体斜长、体高、胸围和管围差异显著(P<0.05);单倍型分析后在群体中发现8种单倍型组合,其中AAA、GGA与南德温杂交肉牛的体高、体斜长、胸围和管围显著相关(P<0.05).由此推断,南德温杂交肉牛GDF10基因3个多态位点和2个单倍型组合与体斜长、体高、胸围和管围显著相关,可以作为肉牛生产性状的候选分子标记,为肉牛遗传资源开发与利用提供科学依据.     

Genetic relationships between the dominant genotypes of Phytophthora infestans in Hokkaido, Japan

The genetic characteristics of the dominant genotypes of Phytophthora infestans in Japan (US-1, JP-1, Japanese A1-A, A1-B) were compared. Differences were evident in the peptidase genotype, amplified fragment length polymorphism, and RG57 DNA fingerprints. Almost all of the fingerprint bands for the Japanese genotype A1-B were also present in JP-1 and Japanese A1-A, and few bands were unique to Japanese A1-B. These results suggest that the Japanese A1-B genotype was generated from sexual reproduction involving Japanese A1-A and JP-1 or related genotypes.     

TaIAA15 genes regulate plant architecture in wheat

Bread wheat (Triticum aestivum L.) is one of the most important staple crops worldwide. The phytohormone auxin plays critical roles in the regulation of plant growth and development. However, only a few auxin-related genes have been genetically demonstrated to be involved in the control of plant architecture in wheat thus far. In this study, we characterized an auxin-related gene in wheat, TaIAA15, and found that its ectopic expression in rice decreased the plant height and increased the leaf angle. Correlation analysis indicated that TaIAA15-3B was associated with plant height (Ph), spike length (SL) and 1 000-grain weight (TGW) in wheat, and Hap-II of TaIAA15-3B was the most favored allele and selected by modern breeding in China. This study sheds light on the role of auxin signaling on wheat plant architecture as well as yield related traits.     

dCAPS markers developed for nitrate transporter genes TaNRT2L12s associating with 1 000-grain weight in wheat

Nitrate transporters(NRTs) are regulators of nitrate assimilation and transport. The genome sequences of TaNRT2L12-A,-B and -D were cloned from wheat(Triticum aestivum L.), and polymorphisms were analyzed by sequencing. TaNRT2L12-D in a germplasm population was highly conserved. However, 38 single nucleotide polymorphisms(SNPs) in TaNRT2L12-A coding region and 11 SNPs in TaNRT2L12-B coding region were detected. Two derived cleaved amplified polymorphic sequences(d CAPS) markers A-CSNP1 and A-CSNP2 were developed for TaNRT2L12-A based on SNP-351 and SNP-729, and three haplotypes were identified in the germplasm population. B-CSNP1 and B-CSNP2 were developed for TaNRT2L12-B based on SNP-237 and SNP-1 227, and three haplotypes were detected in the germplasm population. Association analyses between the markers and agronomic traits in 30 environments and phenotypic comparisons revealed that A-CSNP2-A is a superior allele of shorter plant height(PH), length of penultimate internode(LPI) and peduncle length(PL), B-CSNP2-G is a superior allele of higher grain number per spike(GNS). Hap-6B-1 containing both superior alleles B-CSNP1-C and B-CSNP2-A is a superior haplotype of 1 000-grain weight(TGW). Expression analysis showed that TaNRT2L12-B is mainly expressed in the root base and regulated by nitrate. Therefore, TaNRT2L12 may be involved in nitrate transport and signaling to regulate TGW in wheat. The superior alleles and d CAPS markers of TaNRT2L12-A/B are beneficial to genetic improvement and germplasm enhancement with molecular markers-assisted selection.     

Association Analysis of MUC13 Gene Polymorphisms with Diarrhea in Huanjiang Miniature Pigs

The purpose of the study was to analyze the association between MUC13 gene polymorphisms and piglet diarrhea in Huanjiang miniature pigs.93 diarrhea piglets and 95 healthy controls were included in the study.The MUC13 gene polymorphisms were determined using high resolution melting (HRM),and the results of HRM were verified by direct sequencing.Mutations were compared between diarrhea piglets and healthy controls.SHEsis online platform was used to calculate the haplotypes.There were statistically significant association on G224A site showed significant difference between diarrhea piglets and healthy controls by allele frequencies (P < 0.05),and there were also statistically significant differences between the two groups by genotypes among GG,GA,GG+GA and AA (P < 0.05).But no statistically significant association was found between polymorphisms of A112G,T170C and G164C sites and piglet diarrhea risk (P > 0.05).However,haplotype Ⅹ (GTAC) in the distribution of diarrhea group was extremely significantly higher (P < 0.01).The present data revealed that MUC13 gene G224A site and the haplotypes Ⅹ (GTAC) were associated with reduce risk of piglet diarrhea.     

The importance of haplotype length and heritability using genomic selection in dairy cattle

Reliabilities for genomic estimated breeding values (GEBV) were investigated by simulation for a typical dairy cattle breeding setting. Scenarios were simulated with different heritabilites ( h ²) and for different haplotype sizes, and seven generations with only genotypes were generated to investigate reliability of GEBV over time. A genome with 5000 single nucleotide polymorphisms (SNP) at distances of 0.1 cM and 50 quantitative trait loci (QTL) was simulated, and a Bayesian variable selection model was implemented to predict GEBV. Highest reliabilities were obtained for 10 SNP haplotypes. At optimal haplotype size, reliabilities in generation 1 without phenotypes ranged from 0.80 for h ² = 0.02 to 0.93 for h ² = 0.30, and in the seventh generation without phenotypes ranged from 0.69 for h ² = 0.02 to 0.86 for h ² = 0.30. Reliabilities of GEBV were found sufficiently high to implement dairy selection schemes without progeny testing in which case a data time-lag of two to three generations may be present. Reliabilities were also relatively high for low heritable traits, implying that genomic selection could be especially beneficial to improve the selection on, e.g. health and fertility.     

雷琼牛肌肉生长抑制素基因序列研究

通过PCR方法对18头雷琼牛的MSTN基因进行扩增、测序。编码区序列分析结果表明：雷琼牛MSTN基因比外域瘤牛存在较丰富的多态性,共发现4个突变位点（2个转换,2个颠换）,定义了6种单倍型,群体单倍型多样性较高（0．810±0．057）;分析结果表明：MSTN基因的相关突变的发生可能早于Bos属瘤牛、普通牛、牦牛的分化;在瘤牛种内,我国南方的瘤牛可能是更原始的种群。     

High genetic diversity at the inter-/intra-host level of Cherry leaf roll virus population associated with the birch leaf-roll disease in Fennoscandia

A viral epidemic associated with the Cherry leaf roll virus (CLRV) has emerged in Betula species in Fennoscandia, exhibiting quick and effective spread during the last 15 years. A population genetics approach is chosen in order to characterise the virus diversity and the sources of genetic variation aiming to investigate the epidemiology of the pathogen. In a CLRV population from Rovaniemi urban parks and a population that occurred after infecting young Betula seedlings with scions from the original Finnish trees, the genetic diversity is found to be remarkably high, mixed infections by CLRV variants from different phylogenetic groups are detected in single trees, while recombination is evidenced to occur. The estimated genetic variability is high and the CLRV haplotypes detected exhibit clear clustering and belong to different phylogenetic groups. The structure of the viral population reveals a pathogen with high evolutionary potential assumed to carry on its effective spread.     

中国东方蜜蜂亚种学名订正及生物地理学研究

为明确已认可的中国东方蜜蜂亚种和地理种群,确定一个地方良种提供依据。从中国蜂业生产发展的需要出发,利用东方蜜蜂形态测量和分子数据分析研究。结果表明：自1944年以来,中国东方蜜蜂(Apis cerana F.)已确立有13个亚种,按国际动物命名法规,1970年以后东方蜜蜂的三名法（亚种名）不再具有法律效力,亚种的拉丁学名均系异名,不能再用;东方蜜蜂形态测量研究表明,中国东部地理种群是中华亚种,云南南部地理种群是印度亚种,云南南部地理种群和阿坝种群可以区分,但不能区分云南南部、海南和西藏的东方蜜蜂地理种群;分子数据分析研究表明,中国的东方蜜蜂线粒体DNA单倍型（基因型）和印度、日本、朝鲜一样,都同属亚洲大陆组并无分化。并证实甘肃南部和四川北部阿坝的单倍型（基因型）最为丰富,东方蜜蜂的阿坝地理种群应有存在。     

Identification and classification of S haplotypes in radish (Raphanus sativus)

Radish (Raphanus sativus L.) is a typical cross‐pollinated crop that exhibits obvious heterosis. Self‐incompatibility is an important character for F₁ hybrid breeding of radish. Knowledge of the S haplotypes of breeding lines is very important for breeders to avoid cross‐incompatibility of the parental lines. In the present study, the S haplotypes of 63 radish inbred lines, which were independently cultivated by our research group, were identified by PCR amplification, sequencing and BLAST analyses of the SRK and SLG genes. Finally, fifty‐four inbred lines were classified into 15 class I S haplotypes, including three new types, RsS‐38, RsS‐39 and RsS‐40. Additionally, three class II S haplotypes were identified in nine radish inbred lines. Partial SRK or SLG sequences were completed, such as RsS‐11 Lim (SRK‐S), RsS‐26 (SRK‐K), RsS‐5 Lim (SRK‐K and SRK‐S) and RsS‐9 (SRK‐K). The identified S haplotypes were verified with a cross‐pollination test, and RsS‐9 has weaker self‐incompatibility than other S haplotypes. These information will not only contribute to the production of hybrid seeds but also to the development of new self‐compatible inbred lines, which were advantageous of the production of maintain line and male line in CMS breeding system.