Health, Medicine, & Biotechnology

This method could accelerate research on treatment of some diseases.

A method of studying the functions of all the genes of a given species of micro-organism simultaneously has been developed in experiments on Saccharomyces cerevisiae (commonly known as baker’s or brewer’s yeast). It is already known that many yeast genes perform functions similar to those of corresponding human genes; therefore, by facilitating understanding of yeast genes, the method may ultimately also contribute to the knowledge needed to treat some diseases in humans.

Because of the complexity of the method and the highly specialized nature of the underlying knowledge, it is possible to give only a brief and sketchy summary here. The method involves the use of unique synthetic deoxyribonucleic acid (DNA) sequences that are denoted as DNA bar codes because of their utility as molecular labels. The method also involves the disruption of gene functions through deletion of genes. Saccharomyces cerevisiae is a particularly powerful experimental system in that multiple deletion strains easily can be pooled for parallel growth assays. Individual deletion strains recently have been created for 5,918 open reading frames, representing nearly all of the estimated 6,000 genetic loci of Saccharomyces cerevisiae.

Tagging of each deletion strain with one or two unique 20-nucleotide sequences enables identification of genes affected by specific growth conditions, without prior knowledge of gene functions. Hybridization of bar-code DNA to oligonucleotide arrays can be used to measure the growth rate of each strain over several cell-division generations. The growth rate thus measured serves as an index of the fitness of the strain.

This work was done by Viktor Stolc of Ames Research Center; Robert G. Eason, Nader Pourmand, Zelek S. Herman, and Ronald W. Davis of Stanford Genome Technology Center; Waraporn Tongprasit of ELORET Corp.; and Kevin Anthony and Olufisayo Jejelowo of Texas Southern University. For further information, access the Technical Support Package (TSP) free on-line at under the Bio-Medical category.

Inquiries concerning rights for the commercial use of this invention should be addressed to the Innovative Partnerships Office, Ames Research Center, (650) 604-2954. Refer to ARC-15345-1.

The U.S. Government does not endorse any commercial product, process, or activity identified on this web site.