8 - Genome sequence assembly and annotation

Abstract

The sequencing technology supports sequencing of small DNA fragments only. Therefore, sequencing of the genome is carried out after fragmenting the genomic DNA into small pieces. Reconstructing the original genome sequence from millions of small pieces is a daunting task. In this chapter, the various steps involved in the genome sequence assembly are discussed. It is not possible to reassemble the original genome sequence; instead, the assembled genome sequence shows gaps which are later closed using different gap closing methods. The assembled genome sequence has to be annotated to use it for further study.