A whole-genome assembly of Drosophila

We report on the quality of a whole-genome assembly of Drosophila melanogas ter and the nature of the computer algorithms that accomplished it. Three i ndependent external data sources essentially agree with and support the ass embly's sequence and ordering of contigs across the euchromatic portion of the genome. In addition, there are isolated contigs that we believe represe nt nonrepetitive pockets within the heterochromatin of the centromeres. Com parison with a previously sequenced 2.9-megabase region indicates that sequ encing accuracy within nonrepetitive segments is greater than 99.99% withou t manual curation. As such, this initial reconstruction of the Drosophila s equence should be of substantial value to the scientific community.