非同义

The results show that both of relative rate and synonymous and non-synonymous coden substitution in eudicot clade are significantly higher than those in monocot clade, and the value of dN/ds uncovered possible positive selective pressure in eudicot clade.

结果表明：真双子叶植物分支中SQUA类基因的相对速率和同义与非同义置换位点均显著高于单子叶植物分支；同时，dN／dS值表明真双子叶植物分支中可能存在正选择压力。

Except for variation data, gene descriptions, enzyme information and other biological information for each gene locus are also included. Since RefSeq of NCBI http:∥www:. ncbi. nlm. nih. gov/LocusLink/refseq.

另外，VSD有别于现有的其他变异数据库的主要特点是：一是在基因组、mRNAs和蛋白质三个水平上定位了变异；二是分析了可能影响蛋白质功能的非同义单核苷酸多态性变异(nonsynonymous SNP，nsSNPs)。

Recently polypod ferns have been demonstrated to undergo diversifications in the Cretaceous after the rise of angiosperms. To further test this proposal, an adaptive evolutionary analysis was performed on the rbeL gene sequences of Polypodiaceous ferns under models allowing w (nonsynonymous/synonymous rate ratio) to vary among sites.

为验证蕨类植物在白垩纪适应被子植物兴起而发生分化的观点，本研究以水龙骨科附生蕨类为对象，利用位点间可变ω（非同义替换率d和同义替换率d的比值）模型对其rbcL基因的适应性进化进行分析。

SQUA genes of Dendrocalamus latiflorus were sequenced, and phylogenetic form on SQUA genes in angiosperms was analyzed. Relative rate and adaptive evolution after SQUA gene duplication in recent common ancestor of monocots and eudicots were analyzed using the methods of relative rate test, statistic on synonymous and non-synonymous coden substitution sites and likelihood rate test.

测定了麻竹的SQUA基因序列并分析了被子植物中SOUA类基因的系统发育式样；采用相对速率检验、同义与非同义置换位点统计以及似然比检验方法，分析了单子叶和真双子叶植物最近共同祖先中SQUA基因发生基因重复后的进化速率与适应机制。

The nonsynonymous substitution sites were more than synonymous substitution sites in human, house mouse and pig obviously.

人、家鼠和猪的非同义替换位点数明显高于同义替换位点数。

Over the past two decades, there have been several approximate methods that adopt different mutation models and used for estimating nonsynonymous and synonymous substitution rates based on protein-coding sequences across species or even different evolutionary lineages.

比较基因组分析是研究生物进化关系的基本工具，非同义替换率和同义替换率的计算是研究分子进化动力学的重要内容。在过去的二十多年，基于马尔科夫链的核酸替代模型一直在不断发展。

Nonsynonymous sites were far less than synonymous sites. The ratio of synonymous and nonsynonymous substitution were all less or equal to one manifesting that it did not effected by Darwin positive selection. But some sites affected by negative selection.

非同义突变位点远少于同义突变位点，同义与非同义替代速率比全部小于或等于1，表明MSTN基因编码区序列并未受到达尔文正向选择的影响，却受到一定的负向选择作用。

Over the past two decades, there have been several approximate methods that adopt different mutation models and used for estimating nonsynonymous and synonymous substitution rates based on protein-coding sequences across species or even different evolutionary lineages.

近日，中国科学院北京基因组研究所基因组科学及信息重点实验室通过引入新的参数构造模型，发展了一个新的ka/ks算法，该研究成果在近期出版的 Biology Direct 杂志上发表。比较基因组分析是研究生物进化关系的基本工具，非同义替换率和同义替换率的计算是研究分子进化动力学的重要内容。

All kinds of these study results, including analyzing the nucleotide composition, the amino acid composition, the nucleotide diversity, the synonymous and the nonsynonymous, the transition and the transvertion, the frequencies of the codon used, the construction (including four stems and four loops) of tRNAleu,the phylogeny,suggest that great distinctness present among the genera and small difference even none among species.

在各种分析中(包括核苷酸基本组成分析；氨基酸基本组成分析；核苷酸多样性分析；非同义替代和同义替代分析；密码子使用频率分析；转换与颠换分析；tRNAleu基因的四臂四环二级结构分析；&翻译启始&和&翻译终止&在进化过程中的变化；系统发育分析)，属间的差异相当明显，而种间差异很小甚至是没有任何不同之处。

The average percent value of G C (49.3%) was less than that of A T (50.7%), there was a bias of the content of G, T in the third codon; The number of transition G-A and T-C were 22, 15 respectively, which were higher than that of transition A-G and C-T, the number of tranversion C-A, T-G is 2 respectively, and other tranversion patterns didnt occur; the probability of transition was higher than that of tranversion , Ts/Tv = 9.5-19, there was the highest number of transition in the third codon. The gamma parameter a of the lst,nd and 3rd codon positions were 0.00572,0.01237 and 1.05239 respectively, they showed that there was adifferent substitution rate at different codon position. Frequences of synonymous codon usage were relatively biased. The average rates of synonymous and nonsynonymous substitution were 0.0787, 0.0011 respectively, there was a significant difference between dS and dN (Z = 4.713, p.01), and the low ratio( CD = 0.0284 .3) of dN/dS ratio impled that there were selective constraints against the nonsynonymous sites in cyt-b gene, The distribution of nonsynonymous codon substitution pattern related to Grantharm distance indicated that the purified selection at 2nd codon positions was more intensive than that at 1st codon positions. The phylogenetic trees supported the view of the double origin of Chinese goose, which means that domestic Chinese goose was derived from Anser cygnoides and domestic European goose, and Yili was derived from Anser anser.

碱基含量分析可知，序列的G C含量(49.3％)＜A T含量(50.7％)，密码子第三位点的G、T含量都有较强的偏倚性；序列间G→A和T→C的转换数(22次和15次)高于A→G和C→T的转换数(10次和9次)，C→A、T→G颠换数均为2次，其余颠换模式均未发生；转换数明显高于颠换数，Ts／Tv=9.5～19，密码子第三位点的转换数最高，呈现了相当强烈的转换偏倚性；密码子第一、二和三位点的gamma分布参数α值分别为0.00572、0.01237和1.05239，表明密码子第一位点的替换速率变异最大，第二位点次之，第三位点的替换速率变异相对较小；编码同一氨基酸的同义密码子并非随机使用，表现出一定程度的使用偏倚性；同义替换速率和非同义替换速率分别为0.0787和0.0011，dS与dN值间的差异极显著(Z=4.713，p＜0.01)，而ω=0.0284，明显小于0.3，表明雁属鹅细胞色素b基因序列经历了中度净化选择作用；单步非同义替换(Sing-step nonsymonymous codon substitution，SSNCS)分布模式与Grantharm距离之间的关系说明密码子的三个位点所受的净化选择强度不同；构建的最大简约树与邻接树拓扑结构一致，支持中国家鹅的双起源学说，即除伊犁鹅外的其它中国鹅品种起源于鸿雁，伊犁鹅和欧洲的郎德鹅、莱茵鹅起源于灰雁。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失