Science / Medicine : Master DNA Gene Isolated

The master gene involved in reproducing human DNA has been isolated by a team of Stanford University researchers.

The gene contains the blueprint for one of the major enzymes involved in reproduction of the human genome, a protein called DNA polymerase-alpha.

Scientists have already isolated polymerase genes from such simpler life forms as yeasts, bacteria and viruses. But this discovery is the first for a DNA reproduction enzyme from human cells or any other vertebrate organism, the Stanford team says.

DNA--deoxyribonucleic acid--is the major hereditary molecule of living things. Human cells package their DNA in chromosomes composed of thousands of genes, each spelling out a code for a protein that carries out a specific task for the cell.

Now that the DNA polymerase-alpha gene has been cloned from human cells, scientists hope to investigate the signals that regulate the gene’s expression--when it is turned on or off.

Teresa Wang and her team, who reported the discovery in a recent issue of the journal of the European Molecular Biology Organization, said the similarity of human DNA polymerase to that of distant species suggests that they all may have evolved from a single primordial gene.

She said comparisons of human and viral polymerases might lead to new drugs to fight serious viral infections.