Commonly used vectors for human genome sequencing are:

A bacterial artificial chromosome (BAC) are the plasmids usually applied for the transformation and cloning in bacterial cells, generally E. coli. The usual BAC insert size is around 150-350 Kbp. A similar cloning vector named as PAC has also been developed from the bacterial P1-plasmid. BACs are mostly applied for sequencing purposes in genome projects, as they can be inserted with long size of DNA fragments.

Yeast artificial chromosomes (YACs) are genetically engineered chromosomes modified from the DNA of the yeast, that is further ligated into a bacterial plasmid. By insertion of large DNA fragments, around 100–1000 Kbp in size, the inserted sequences are usually cloned and then the physical mapping is employed by a process known as chromosome walking.