CBSE NEWS

Study highlights the importance of "junk DNA" in higher eukaryotes

Friday, July 15, 2005
Written by Maria Smit

Genome annotation from UCSC Genome Browser

A landmark comparative genomics study appearing in the journal Genome Research describes the most comprehensive comparison of conserved DNA sequences in the genomes of vertebrates, insects, worms, and yeast to date. Adam Siepel, graduate student in David Haussler’s laboratory, led the study.

One of their major findings was that as organism complexity increases, so too does the proportion of conserved bases in the non-protein-coding (or “junk”) DNA sequences. This underscores the importance of gene regulation in more complex species.

The paper also reports exciting biological findings regarding highly conserved DNA elements and the development of a new computational tool, called phastCons, for comparing several whole-genome sequences. It was authored by multiple investigators from leading research institutions, including Penn State University, Washington University School of Medicine Baylor College of Medicine, and UC Santa Cruz.

For genomic scientists, the current study is a major contribution to the field. Not only will the new bioinformatics tool phastCons help researchers identify evolutionarily conserved DNA elements, the reported conserved elements are represented as conservation tracks in the UCSC Genome Browser. “With phastCons and with the conservation tracks in the browser,” says Siepel, “we’re trying to make it as easy as possible for researchers to home in on functionally important DNA sequences.”