生物信息中的reads contig scaffold N50 具体点测序深度

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/03 05:19:53
生物信息中的reads contig scaffold N50 具体点测序深度

生物信息中的reads contig scaffold N50 具体点测序深度
生物信息中的reads contig scaffold N50 具体点
测序深度

生物信息中的reads contig scaffold N50 具体点测序深度
Contigs and scaffolds
Contig The result of joining an overlapping collection of sequences or clones.
Scaffold The result of connecting contigs by linking information from paired-end reads from plasmids,paired-end reads from BACs,known messenger RNAs or other sources.The contigs in a scaffold are ordered and oriented with respect to one another.
Fingerprint clone contigs Contigs produced by joining clones inferred to overlap on the basis of their restriction digest fingerprints.
Sequenced-clone layout Assignment of sequenced clones to the physical map of fingerprint clone contigs.
Initial sequence contigs Contigs produced by merging overlapping sequence reads obtained from a single clone,in a process called sequence assembly.
Merged sequence contigs Contigs produced by taking the initial sequence contigs contained in overlapping clones and merging those found to overlap.These are also referred to simply as 'sequence contigs' where no confusion will result.
Sequence-contig scaffolds Scaffolds produced by connecting sequence contigs on the basis of linking information.
Sequenced-clone contigs Contigs produced by merging overlapping sequenced clones.
Sequenced-clone-contig scaffolds Scaffolds produced by joining sequenced-clone contigs on the basis of linking information.
Draft genome sequence The sequence produced by combining the information from the individual sequenced clones (by creating merged sequence contigs and then employing linking information to create scaffolds) and positioning the sequence along the physical map of the chromosomes.
N50 length A measure of the contig length (or scaffold length) containing a 'typical' nucleotide.Specifically,it is the maximum length L such that 50% of all nucleotides lie in contigs (or scaffolds) of size at least L.

Scaffold N50与Contig N50的定义类似。Contigs拼接组装获得一些不同长度的Scaffolds。将所有的Scaffold长度相加,能获得一个Scaffold总长度。然后将所有的Scaffolds按照从长到短进行排序,如获得Scaffold 1,Scaffold 2,Scaffold 3...………Scaffold 25。将Scaffold按照这个顺序依次相加,当相加的长度达到...

全部展开

Scaffold N50与Contig N50的定义类似。Contigs拼接组装获得一些不同长度的Scaffolds。将所有的Scaffold长度相加,能获得一个Scaffold总长度。然后将所有的Scaffolds按照从长到短进行排序,如获得Scaffold 1,Scaffold 2,Scaffold 3...………Scaffold 25。将Scaffold按照这个顺序依次相加,当相加的长度达到Scaffold总长度的一半时,最后一个加上的Scaffold长度即为Scaffold N50。举例:Scaffold 1+Scaffold 2+ Scaffold 3 +Scaffold 4 +Scaffold 5=Scaffold总长度*1/2时,Scaffold 5的长度即为Scaffold N50。Scaffold N50可以作为基因组拼接的结果好坏的一个判断标准。

收起