PMC:55322 / 1973-3246 JSONTXT

{"project":"2_test","denotations":[{"id":"11516338-9371743-44573035","span":{"begin":566,"end":567},"obj":"9371743"},{"id":"11516338-1881886-44573036","span":{"begin":1042,"end":1043},"obj":"1881886"}],"text":"As of late 2000, the public human sequence was primarily based on approximately 24,000 accessioned bacterial artificial chromosome (BAC) clones covering 97% of the euchromatic portion of the genome [6]. The sequence of these clones is approximately 93% complete to at least 4-fold coverage [7]. Thirty percent of the genome is in finished form, including the entire sequence of chromosomes 21 and 22 [7]. These clones represent the most complete sequence information available, with overlapping clones positioned on a framework map using restriction fingerprinting [8]. However, reduction to a single consensus sequence permits placement of genes and other chromosomal structures in their proper positional context. Recently, the consortium has distributed a working draft assembly of the entire genome that removes redundancies, orients sequence fragments and clearly indicates gaps arising from sequencing and assembly. The total assembled length is 3.08 billion bp - about 4% smaller than estimates of genome size based on flow cytometry [9], presumably due to the exclusion of constitutive heterochromatic regions and centromeres. Major gaps (50-200 kilobases (kb)) comprise 16% of the assembly, whereas minor gaps (100 or fewer bp) and low-quality calls comprise 0.5%."}