Question

Describe the methodologies and procedures used to sequence the Arabidopsis genome. Why were Bacterial Artificial Chromosome (BAC) clones so useful in the objective of sequencing the Arabidopsis genome? In broad terms, also describe how this procedure differs from the approaches currently used to sequence genomes using Next Generation Sequencing.

Answer 1

The procedure used to sequence Arabidopsis genome-

1. Isolation of Arabidopsis genome
2. Digesting the genome into smaller fragments
3. Preparation of DNA library by cloning the DNA digests into plasmids
4. sequencing the DNA library by nucleic acid sequencing- sanger sequencing

The bacterial artificial chromosome has an insert size of 150–350 kbp. These are used to sequence genomes of organisms. In this a short fragment of DNA is amplified and inserted into BACs, and then the recombinant BAC is sequenced. The sequences are then arranged in silico, this gives the sequence of the organism.

BACs are faster, less laborious.

NGS produces shorted reads compared to BAC sequencing.