Detour: Pitfalls of Assembling Double-Stranded DNA

Handling reads in double-stranded DNA

To assemble real genomes, bioinformaticians must handle reads from both DNA strands without knowing in advance which strand each read comes from. To address this challenge, they first add the reverse complement of each read to the collection of reads, effectively doubling the number of reads. In an ideal world, the de Bruijn graph formed from all these reads would consist of two (topologically identical but differently labeled) connected components, one for each DNA strand (see figure below).