湖羊蛋白酶遗传型结构及系统地位的研究

用“中心产区典型群随机抽样”的方法 ,对湖羊品种进行遗传检测。在所检测的 12个位点中的 11个 (Alb、Tf、Alp、L ap、Ary- Es、Hb- β、X- p、CA、Cat、L y和 Ke)具有多态性 ,仅 Po位点为单态 ,多态座位比例为 91.6 7% ,在 2 7个等位基因中 ,只有 Po F、Tf A、Tf F、Hb- βA、CAF 和 Ke L 的估计可靠程度分别为 0 .5 2 2 2 ,0 .74 5 8,0 .5 2 2 2 ,0 .6 2 12 ,0 .8990和 0 .90 70外 ,其余 2 1个等位基因估计可靠程度均在 0 .95 45以上。说明“中心产区典型群随机抽样”在特定遗传背景下是一种有效的抽样方法。湖羊的平均杂合度比国内其他绵羊种群偏低 ,而与国外其他群体相比 ,平均纯合度偏低。引用国内外 14个绵羊群体的相同资料 ,根据血液酶和其他蛋白质变异的 10个基因座位共计 33个等位基因的频率 ,进行系统聚类分析 。

Genetic Structure of the Oriental River Prawn (Macrobrachium nipponense) from the Yangtze and Lancang Rivers, Inferred from COI Gene Sequence

This study analyzed nueleotide sequences from the mitochondrial eytochrome oxidase submit （COI） gene region （450 bp） to investigate the genetic structure of the oriental river prawn （ Macrobrachium nipponense ） among nine populations from the Yangtze and Lancang Rivers. A total of 79 individuals were collected for this work. Eighty-nine nucleotides were found to be variable, resulting in 46 haplotypes. Among the nine populations, the population from Kunming shows the greatest level of variability （h = 1.000, π = 0.028）, whereas the population from Cbongqing exhibits the lowest level of variability （h = 0.700,π = 0.008）. Analysis of molecular variance suggested that of the total genetic diversity, 9.66% was attributable to inter-population diversity and the remainder （90.34%） to differences within populations. A molecular phylogenetic tree constructed using the Neighbor-joining （N J） method showed that the 46 haplotypes were assigned to two clades associated with geographic regions. These results provide basic information for the conservation and sustainable exploitation of this species.

Genetic structure of wintering Hooded Cranes (Grus monacha) based on mitochondrial DNA D-loop sequences

The Hooded Crane (Grus monacha) is a waterbird wintering in the wetlands of the middle and lower reaches of the Yangtze River, China. The gradual habitat loss resulting from wetland degradation may have posed negative effects on the structure of our wintering populations. For its effective protection, it is important to conduct an intensive study on the genetic structure of this population. A total of 221 faecal samples, nine feather samples and four muscle samples of Hooded Cranes from four wintering populations, i.e., from Caizi Lake and Shengjin Lake in Anhui, Poyang Lake in Jiangxi and Chongming Dongtan in Shanghai, were collected for this study. Full-length 1103–1104 bp mtDNA D-loop sequences from 72 samples were amplified using PCR. Based on our amplified D-loop sequences and the sequences of two individual birds obtained from GenBank (AB017625 and AB023813), we analyzed the genetic structure of these four wintering Hooded Crane populations. Twenty six variable sites were found among 72 target sequences in the four wintering populations and 23 haplotypes were defined. Genetic diversity analyses showed that the haplotype diversity of Hooded Cranes was 0.823 ± 0.042 with a nucleotide diversity of 0.00157 ± 0.00021. The FST values of the four populations show that there is no significant genetic differentiation among the populations of Hooded Cranes wintering in the middle and lower reaches of the Yangtze River. Tajima’s D and Fu’s tests suggest that the Hooded Crane populations may have experienced population expansion in their evolutionary history.

Analysis on Genetic Structure of Spartina alterniflora Populations in China Based on EH277045-derived Sequence

[Objective] This study aimed to analyze the genetic structure of eight populations of Spartina alterniflora in China at the nuclear DNA level.[Method] The EH277045-derived sequences were amplified from 75 samples in 8 populations and directly sequenced.Nucleotide diversity,haplotype diversity,the mean value of Nei＇s genetic distance,genetic differentiation index FST and other genetic parameters were calculated to estimate the genetic diversity and genetic differentiation of S.alterniflora populations in China.[Result] 75 samples were divided into 25 haplotypes by 28 polymorphic sites.Relatively high nucleotide diversity（π=0.011） and haplotype diversity（Hd=0.794） were detected.The mean value of Nei＇s genetic distance and genetic differentiation index FST among eight populations were 0.056 and 0.222,respectively,the Nei＇s genetic distance ranged from 0.000 to 0.189 and FST ranged from 0.000 to 0.444 between each pair of the eight populations.AMOVA result revealed that 79% and 21% of the total genetic variation was partitioned within and among S.alterniflora populations,respectively.[Conclusion] At the nuclear DNA level,there were a relatively high level of genetic diversity and a relatively low level of genetic differentiation among S.alterniflora populations in China,and the genetic diversity existed mainly within rather than among populations.

The comparison between allozyme and RAPD makers for the population genetic structure analysis of scallop Chlamys farreri

To compare genetic markers for population genetics analysis, allozyme electrophoresis and random amplified polymorphic DNA （RAPD） were used to detect the genetic structure of scallop Chlamysfarreri population. Thirteen enzymes （MDH, ME, IDH, GPI, PGM, PEP-LG, PEP-pp, ACP, AK, PK, AAT, SOD, EST） in three butter systems （TC, pH6.9; TMME, pH 7.4; and EBT, pHS.9） were selected and 22 loci were used for the analysis, among them 7 loci （Gpi, Pgm, Pep.m-l, Pep.pp. Aat-2, Est-2, Est-3） were polymorphic which attributed 31.82% to the total. The average of heterozygosity was 0.113 and most of the studied loci showed heterozygote deficiencies. The same specimens were investigated using 10 arbitrarily selected primers （10-base）. Twenty two of 54 RAPD fragments were polymorphic with average heterozygosity of 0.194. The result indicated that the two types of markers reflected a consistent trend in the parameter values of genetic diversity of the population, but RAPD revealed more information of genetic variation than allozyme electrophoresis.

Hv-SEMIGROUP STRUCTURE ON F2-OFFSPRING OF A GENE POOL

Mendel, the father of genetics took the first steps in defining ＂contrasting characters, genotypes in F1 and F2... and setting different laws＂. The genotypes of F2 is dependent on the type of its parents genotype and it follows certain roles. Purpose of this paper is to analyze the second generation genotypes of monohybrid and a dihybrid with a mathematical structure. We use the concept of Hv-semigroup structure in the F2-genotypes with cross oper- ation and prove that this is an Hv-semigroup. We determine the kinds of number of the Hv-subsemigroups of F2-genotypes.

You are never alone: crosstalk among epigenetic players

Different cell types in a certain organism contain the same genome while running diverse transcription programs. This is controlled by epigenetic information, including DNA modifications, histone modifications, histone variants, non-coding RNAs, and chromatin architectures. Interestingly, recent progresses revealed extensive crosstalks among these epigenetic players. We discuss here how epigenetic players coordinate with each other to maintain epigenetic identities in mammal cells. More exciting researches are expected to expand our understanding regarding the epigenetic regulatory network.