Bacterial artificial chromosome (BAC) libraries are an important tool for p
ositional cloning, gene analysis and physical mapping. During studies using
BAC clones, it is often necessary to organize them into contiguous sequenc
es (contigs). To finalize, join and extend the contigs, both cloning and se
quencing of the ends of the inserts are required. Here, we describe a low-c
ost accessible, fast and powerful method for the routine isolation of BAC e
nds. This method allows the isolation of 20 BAC clone ends in one day. The
analysis of the ends reveals fragment sizes compatible with sequencing, and
the structure of these clones allows the sequencing of both ends using the
same plasmid. Moreover, long end fragments can be sequenced in both direct
ions.