Designer Bags and Designer Chromosomes

      Imagine your pet carrying a genome assembled by a group of scientists. This situation probably sounds like the beginning of a science fiction movie, but it may become a reality. A new report in Science describes the creation of a synthetic chromosome in baker's yeast (Saccharomyces cerevisiae).

      Jef Boeke's group at New York University generated a synthetic version of chromosome 3, one of the smallest chromosomes in the genome of baker's yeast. In creating this chromosome, they eliminated transposons (DNA sequences
that have the ability to move around the genome) and introns (non-coding
regions of DNA). Boeke's group also designed custom DNA sequences

Electron micrograph of human chromosomes.

Courtesy: Andrew Syred, York University, Canada

that they incorporated into the yeast chromosome with the aid of homologous recombination, which involves the exchange of native yeast DNA sequences for the custom-made counterparts. Yeast cells carrying this chromosome were able to mate and behave normally, which indicates the artificial DNA is not deleterious to the cells. Additionally, artificial DNA incorporated into this synthetic chromosome allowed yeast cells to undergo genetic recombination, which can add or delete specific segments of DNA.

      Craig Venter announced his team's creation of the first synthetic bacterium in 2010, and this innovation quickly grasped the attention of the public. With the advent of these synthetic organisms, scientists have claimed that the formulation of vaccines, medications, and biofuels can be less expensive and time-consuming. It may take several years for scientists to engineer these organisms, but this possibility opens the door for additional advantages of these systems to be explored.