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全部话题 - 话题: sequence
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a***e
发帖数: 1010
1
you can download the cosmid sequence to your computer, and then according
to the position of tag-24 on that cosmid, you can select out the sequence
you need.
however, I never did that way. I prefer wormbase.

give
based
w******a
发帖数: 26
2
来自主题: Biology版 - next generation sequencing technology
Agree with LZ, sequencing cost may not be a problem in the future. PacBio
claims to sequence the human genome with $100, GnuBio claims $30 in the
future. What will be the biggest problems are data analysis and
interpretation. A regular lab probably won't have the computing resources
for whole genome analysis, so people are talking about cloud computing and
offer a genome browser interface for users, like DNAnexus. Interpretation
is also a formidable task. There will be so many variants with un
Y**I
发帖数: 444
3
来自主题: Biology版 - next generation sequencing technology
NGS has higher error rate than Sanger, however, the deep sequencing (high
coverage) is capable of improving
it.
As matter of fact, a few private companies already provide "personal
sequencing", which is used by physicians
as reference for prescriptions (personal drugs). FDA actually is trying hard
to regulate these services by, for
example, implementing "prescription needed" policy for the service
providers when customers knock at the
doors.
Here comes an interesting question: what kinda physic
s******y
发帖数: 137
4
来自主题: Biology版 - next generation sequencing technology
454,Illumina, SoLID都用过(更精确的说都做过数据分析)我也说两句吧,
454
好处是长度最接近sanger sequencing, 很多现成的工具都可以用。
精确度可能是三个里最低的,特别对多个单碱基重复非常差是他的致命缺点。还有测序
费用比较高。
Illumina现在基本就是Next gen sequencing 的代名词了。好处和缺点都楼主都说的比
较清楚了。
SoLID测序费用比Illumina低,精确度由于他特有的记录碱基方式比illumina也要高不
少。
缺点是color space 的概念比较复杂,我开始的时候错把doule encoded的序列直接当测序结果来
分析浪费了很多时间。很多对Illumina开发的工具不能直接用在SoLID上。 还有就是应
该要有reference序列才能做到base calling(如果错了请大家指正)。反正我们实验
室现在基本还是回到Illuminas上了。
对新的技术不看好Helicos, 长度短错误率高,RNA直接测序从2009年1月就说马上就有
了但现在还没有地方能做(Harvard 目前只做DNA测序)
BioP
B********6
发帖数: 43
5
用的是C. elegans
开始我是在NCBI 上找的,给的pqn-46 gene's sequence 是 complement 6941825-
6944674. 可是因为有个字:complement, 我就不知道该如何算pqn-46's promoter
sequence的长度了。pqn-46's upstream gene is F57B9.3, from 6940113-6941672.
请懂得大侠相助,有包子答谢!
G***G
发帖数: 16778
6
来自主题: Biology版 - sequencing principle
any article about sequencing principle?
next generation sequencing.
easy to understand
w******e
发帖数: 1187
7
复杂的弄不来,就想搞点最简单的:现在所有sequence在一个excel里,
想请教如何extract出single sequence,做些alignment,cluster之类的分析
多谢!!
r********7
发帖数: 229
8
最近一期Sci Transl Med中Carrier Testing for Severe Childhood Recessive
Diseases by Next-Generation Sequencing报道用NGS检测448 severe
recessive childhood diseases。结果发现NGS的sensitivity和specificity都很
好(用array的方法验证);平均每sample有 2.8个突变;还发现之前文献中报
道的与疾病相关的突变不对或不全...
http://stm.sciencemag.org/content/3/65/65ra4.full
小弟看了很感兴趣,有几个问题请教大侠们
文章中用的是Illumina GAIIx (SOLiD辅助)来检测,如果用454的机器来测序,
效果会如何?根据dfbb以前的牛文
http://mitbbs.com/article_t1/Biology/31375537_0_1.html
454可以测的序列更长(500 vs 50 of Illumina),不过出错率高些。但是如果可
以deep sequen... 阅读全帖
f**********e
发帖数: 1994
9
同意,需要统计和计算机的混合背景。高效 sequence alignment
还是 assembly 都需要 CS (q-gram? Smith-waterman?
Hashing? db graph? overlapping?), 解读 aligned 过的
资料(最简单的:这个 mismatch 是 sequencing error 还是
variant? 如果 3X 的 coverage 分不出来,多大的 coverage
才中?)
我两个背景都没有,所以俺才能干这行。 :)
m******h
发帖数: 28
10
Did anybody know if the trans-acting factor binding consensus has direction.
For example, if the Smad3 recognizes the 5'CAGA3' sequence, can it
recognize the 5'TCTG3' sequence? Are there any experimental evidences? Thanks
for answering.
s********e
发帖数: 323
11
我是学统计的,对miRNA一点也不懂。
我们的数据里有一些miRNA以及sequence信息,都是mature miRNA。然后我们找了个别
人发表的数据,想在里面找和我们的miRNA match的。但是发现别人的数据里都是
precursor,而不是mature miRNA,然后给的sequence和我在网上找到的相应的miRNA
precursor的也不一样。请问如何来判断这些miRNA是不是和我们的一样?仅仅看名字可
靠吗?比如hsa-mir-1-1就一定对应也hsa-mir-1吗?
多谢了!
f*******g
发帖数: 35
12
麻烦问一下 大家谁在用pVR1012 这个vector?我在网上查到 这个vector 是Vical,
Inc. 公司的, 但没有相关的信息阿! 这个vector的reverse and forward
sequencing primer sequence是什么呢?
谢谢!
m*********n
发帖数: 215
13
来自主题: Biology版 - 求科普Next Generation Sequence
其实whole genome sequencing的specificity如果和exonme sequencing相比的话是非
常接近的。
l*****g
发帖数: 263
14
em. I feel this may be a better way to go.
Current question is: we know a binding pattern, and we wanted to know the
potential binding sites on a long sequence. Very traditional question.
Thanks and I will try it as well.

HMMER
g*******8
发帖数: 6
15
来自主题: Biology版 - 问个sequencing的初级问题
既然可以用pcr product和primer直接做sequencing,那为什么有时还要用TOPO
cloning先clone,然后再做RCA, 最后用RCA product 和primer来做sequencing呢?
多谢指教!
n***w
发帖数: 2405
16
来自主题: Biology版 - 问个sequencing的初级问题
PCR product is a heterogenous population which contains many copies of DNA.
Sequencing may give you false positive result. BTW, if you just send PCR
product and primers for sequencing, you cannot get full length (you will
lose ~60 at both ends.)
But after TOPO cloning, it only contains single copy of DNA.
c**i
发帖数: 6973
17
来自主题: Biology版 - Brand New Method of DNA Sequencing
Nicholas Wade, Decoding DNA With Semiconductors; New machine offers faster,
cheaper way to sequence genome. New York Times, July 21, 2011.
http://www.nytimes.com/2011/07/21/science/21genome.html
Excerpt in the window of print: It will take years to make sense of much of
teh data a novel technology reveals.
My comment:
(a) Techmnology. Ion Torrent, undated.
http://www.iontorrent.com/technology-scalability-simplicity-spe
Go to "How does it work?" in the left column. Clcik "Read more" and you
reach... 阅读全帖
s******y
发帖数: 137
18
来自主题: Biology版 - DEEP SEQUENCEING? ANY SUGGESTION
如果只是RNA表达的差异上不一定现在要跳deep sequence,比起microarry来说在一般
模式生物上没有太大优势。但是缺点是如果同样一组做三个重复价钱要贵不少(bar
coding 还是比较麻烦而且又多一层bias)。而且现在没有太好的分析软件,如果没有
一定的command line的经验的话分析起来还是比较费劲的。
deep sequence还是在非模式生物和一些比较特定的实验设计(alternative splicing,
allele specific expresion,etc)下优势比较明显吧。
just my two cents.
m***T
发帖数: 11058
19
来自主题: Biology版 - DEEP SEQUENCEING? ANY SUGGESTION
关键是现在的high throughput sequencing从library的制备,到sequencing本身再加
上后期的data处理都没有golden standard,错误率受各种因素的影响比较大,所以没
有其它validation方法,数据的准确性还不足以让大多数人信服。如何有效提高准确性
是整个NGS市场(包括array)面临的一个很大挑战。
g***y
发帖数: 201
20
1. A lot of expression vectors contain SV40 pA or BGH pA. You can simply
PCR adding those sequence right after the stop codon.
2. It all depends on how you design your KI allele. If your KI allele is
only to replace one exon, then you don't need to worry about anything. If
you are to insert a cDNA sequence right at the 1st exon,
then you may have to worry about non-sense mediated dacay. In this case, it
would be safer to add an exogenous pA.

allelle
s********n
发帖数: 248
21
来自主题: Biology版 - 求科普RNA-sequencing
http://gtac.wustl.edu/services/sequencing/analysis-pipelines.ph
RNA-Seq
TopHat – align raw sequence reads to the reference genome. Tophat maps across splice junctions.
Cufflinks - assemble the transcripts, estimate their abundance and test for differential expression in RNA-Seq samples. Currently gene abundance is restricted to annotated genes and transcripts.
C*******e
发帖数: 4348
22
这个就是pyrotag sequencing
只不过pyrotag sequencing的通用引物上还放了barcode
y******8
发帖数: 1764
23
This means the chip should have 100M wells for Exome, and more than 300M
wells for the genome sequencing.
With the current size of Ion sphere beads, the chip should be huge.
Any inside news for the ion proton chip specifications?
y******8
发帖数: 1764
24
Life should be able to do it. More wells in a chip are not a problem for
sequencing speed, and are not hard at all to manufacture.
They only need to make a bigger machine to handle bigger chips.
P****d
发帖数: 564
25
Nice! When can we just spit on the chip and get our genome sequenced?
t*d
发帖数: 1290
26
和Illumina 将推出的新版 Hi-SEQ比,不计sequencer本省,每个 genome 测序所需的
费用相差大么?
s******s
发帖数: 13035
27
大家升级这么快,贵的机器不容易卖,除了大的sequencing center,
大家宁愿耗材贵点或者throughput低点, 可以等一年升级新产品啊

法。
a******e
发帖数: 119
28
【 以下文字转载自 Statistics 讨论区 】
发信人: annoname (summer), 信区: Statistics
标 题: 做 Next generation sequencing 这个方向怎么样?
发信站: BBS 未名空间站 (Fri May 18 13:48:07 2012, 美东)
现在二年级,统计专业。要选导师选方向了。自己是生物背景的。系里有个老师是做
Next generation sequencing 数据分析这个方向的,我比较感兴趣。请问班上的大牛们
,这个方向在工业界和学术界怎么样?
c********b
发帖数: 363
29
来自主题: Biology版 - 求教:Deep sequencing的data convert
不好意思,是小RNA的deep sequencing (不是genome sequence),后面的number是表
示read number(abundance)。
我就想把它变成fasta或者其他可以被下游软件识别的格式。

ref
j**W
发帖数: 89
30
来自主题: Biology版 - Help: mouse genotyping by sequencing
另外一个位点(见图),也是heterozygous.当时用P3-P4做PCR, gel purified
band with size of targeted allele, but not wild type allele (两个分得很开)
, P1做sequencing得到wild type sequence,虽然读的序列很短.当时真是晴天霹雳!
有多大可能性是我图上画的mis-targeted的情况?用homozygous genomic DNA做nested
PCR会有不一样的结果吗?
j**W
发帖数: 89
31
来自主题: Biology版 - Help: mouse genotyping by sequencing
见新图并更正。
Sequencing was done with P2, which is within Exon 1. The resulting sequence
include region A (part of Exon 1 starting from P2 to before NotI site)
followed directly by region C (Intron 1 after the AscI site). NotI and AscI
are the enzymes used to put the construct together.
现在清楚了吗?
k*****8
发帖数: 91
32
最近问别人要了几个vector,给我发的sequence是txt文件,下载打开之后格式比较乱
,如果直接在浏览器里面打开格式比较整齐,但是就像附图一样,两条链的信息都有,
还有的地方有一些标注,但是这样查看搜索都不是很方便,想问问大家知不知道用什么
软件可以打开或者编辑这种格式的vector sequence, 比如可以把这个序列拼接起来方
便搜索等等,先谢过了~~~
k*****8
发帖数: 91
33
I do have ape on my laptop. However, when I tried to copy-paste the whole
double strand sequence into ape, it only remove part of the labels. There's
no way to get single strand sequence either. Is there something I was
missing from ape? Thanks
S*********e
发帖数: 127
34
来自主题: Biology版 - exome sequencing realighment
what we have: mutant whole exome sequencing reads, three reference whole
genome sequence databases with SNPs.
What we want: sorting out point mutations in exons.
We are looking are a suitable aligner/program to sort out the high peak of
linkage loci.
Thanks,
y**q
发帖数: 570
35
如果我从ncbi search出突变基因sequence,想copy 还有mutant gene sequence 片段
前后 500bp 到相关primer design soft website 运行,找找出primer design
software 推荐 primer. 请问相关 primer design software link 推荐, 多谢!
l****1
发帖数: 168
36
We need a 10-mer DNA sequence which won't hybridize with any human mRNA
sequence. But I design a few and always can find it 100% match in human mRNA
database. Can anyone help me on this? Thanks
l***y
发帖数: 638
37
来自主题: Biology版 - about sequencing pCMV
cmv的sequence google一下就有了,很多测序公司都有cmv的引物
实在不行用你gene的sequence去搞几个primer测几段overlap的自己拼

But
?
i*******i
发帖数: 145
38
assembly是sequencing中最难的问题(且不说重要性,这个见仁见智)。如果能解决
assembly,那么就可以解决任何问题。
我说的science的意思是,不计成本的情况下找到最准确的结果。有足够coverage的条
件下,pacbio完美解决一切sequencing的问题。准确度的问题可以通过多次测序取
consensus解决,理论上达到0 error rate。
对于oxford,我说了这个engineering的问题。这个问题迟早会解决。但是等一段时间
是肯定的(个人目测至少1年以上)。
g***j
发帖数: 40861
39
来自主题: Biology版 - 请教一个sequence diversity 的问题
比如说一段DNA 有sequence variation
然后我NGS测序,读到10000个有效read,然后一做alignment,完全一样的归成一种,
一共得到1000种
我能不能简单的说这段DNA的 sequence diversity 是1000/10000=0.1 ?
n********b
发帖数: 27
40
There is a position opening for a Principal Lab Assistant in a new Genomics
Center of a University located in southern California. The position is
supported by hard money with good benefit plans. Please send your resume
and email to [email protected]
/* */, if you are interested. Thanks!
------------
Principal Lab Assistant
Center for Genomics
Job descriptions:
1. Performs bench work related to research projects using different genomic
technologies including next-generation sequencing (N... 阅读全帖
c*******e
发帖数: 5818
41
有一个allele,我们做了TALEN,因为没有合适的限制性酶,用了T7, T7 indicate 可
能有“indel",我的问题是,如何确认这个”indel",不知直接deep sequence之类可
以不,不太想做PCR TA clone,然后做regular sequence。谢谢。
h****n
发帖数: 333
42
同意,TALEN完全没必要用deep sequencing的方法确认indel,就普通的PCR条带直接
sanger测序然后分析足够了
序列分析用MutationSurveyor也可以看indel
deep sequencing不止是有钱任性,看indel还不如普通的sanger测序准确,何苦
z**********5
发帖数: 63
43
本人(生物统计PI)和同事(流行病PI)联合招聘一个计算生物/生物信息学博后,工
作方向为 tumor sequencing. 主要职责为(1)和本人一起开发算法 (clonal
evolution, integrative genomic analyses)(2)lead 大型 tumor sequencing
project (200- 500 tumor samples, breast cancer). NIH的薪水和福利还是很不错的
。另外,NCI考核PI一个的关键指标就是mentoring; 因此,我们会想尽办法让你
productive. 请感兴趣的同学站内联系。NIH只能提供J1签证;如果你特别unique,NIH
能够提供H1B签证(但是很难)。计算生物学/数量遗传/进化/生物信息背景的申请人优
先考虑。
b********w
发帖数: 334
44
From Frontline Genomics.
A Collaborative Effort: Meet the Company Empowering Personal Sequencing
http://www.frontlinegenomics.com/interview/6716/collaborative-effort-meet-company-empowering-personal-sequencing/
b********w
发帖数: 334
45
我们的sequencing是外包的,成本,折旧和我们没有直接关系,但是我们对质控有很强
的要求。我们的supplier是CLIA Lab, 所有的sequencing, sample prep的流程都要按
照CLIA的流程走,所有的步骤都要有paper trail。除了deliver 数据,还有他们lab
director的签名的tech report. 我们不是临床样品,结果不能用于临床,但是我们对
样品处理的要求是和临床样品是一致的。
我们的supplier其实很愿意和我们合作,我们的样品多,而且处理完全相同, 时间要
求也不是很紧,成本可以做的很低的
75x是我们的最低要求,是指after mapping, filtering,removing duplicates的有效
reads, 原始数据一般要>130x, 而且我们对uniformity也有要求,和75x必须同时达到
。 我们接收到的数据目前最低97x, average 120x,好到我们都很吃惊。
其实business model, 测序成本啥的对消费者来说没啥关系. 数据质量高,质控要求严
格,对数据不要求所有权(Y... 阅读全帖
b********w
发帖数: 334
46
From Frontline Genomics.
A Collaborative Effort: Meet the Company Empowering Personal Sequencing
http://www.frontlinegenomics.com/interview/6716/collaborative-effort-meet-company-empowering-personal-sequencing/
b********w
发帖数: 334
47
我们的sequencing是外包的,成本,折旧和我们没有直接关系,但是我们对质控有很强
的要求。我们的supplier是CLIA Lab, 所有的sequencing, sample prep的流程都要按
照CLIA的流程走,所有的步骤都要有paper trail。除了deliver 数据,还有他们lab
director的签名的tech report. 我们不是临床样品,结果不能用于临床,但是我们对
样品处理的要求是和临床样品是一致的。
我们的supplier其实很愿意和我们合作,我们的样品多,而且处理完全相同, 时间要
求也不是很紧,成本可以做的很低的
75x是我们的最低要求,是指after mapping, filtering,removing duplicates的有效
reads, 原始数据一般要>130x, 而且我们对uniformity也有要求,和75x必须同时达到
。 我们接收到的数据目前最低97x, average 120x,好到我们都很吃惊。
其实business model, 测序成本啥的对消费者来说没啥关系. 数据质量高,质控要求严
格,对数据不要求所有权(Y... 阅读全帖
r**********e
发帖数: 587
48
其实是个很基本的问题。
我们一般都用pcr-sanger sequencing来测比如有没有突变,只是看有或者没有
我现在需要知道这个位点的突变的相对精确的allele frequency,比如20% vs 50%的区别
那么我直接sanger sequencing,ab1文件的两种颜色的peak height的差别是否能真实
反映allele frequency的差别呢?
e*******o
发帖数: 4654
49
如果你是想学习sequence的技术 比如怎么提高seq精度 长度 这个估计不好找实验室
如果你想学习处理sequence相关的分析 学linux python或者上cs的课 这样的工作大把
biostar 论坛很多招薄厚的帖子
e*******o
发帖数: 4654
50
如果你是想学习sequence的技术 比如怎么提高seq精度 长度 这个估计不好找实验室
如果你想学习处理sequence相关的分析 学linux python或者上cs的课 这样的工作大把
biostar 论坛很多招薄厚的帖子
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