Current sequencing technology can only determine about 600
consecutive base pairs of DNA in a single read. Hence, to
obtain the sequence of a larger stretch of DNA, one must
randomly chop it up into small pieces, which are then read
and "assembled" (so-called shotgun sequencing). One strategy
has been to assembly 150 Kps at a time, in a slow-but-sure
approach. Celera Genomics favors "Whole Genome Shotgun
Assembly" (using a "double-barreled" shotgun), relying
heavily on bioinformatics to assemble the whole genome
in-silico within a short time-frame.