The mapping and sequencing of the human genome, now nearing completion, marks a historic point in biology and the beginning of equally exciting discoveries as scientists make increasing sense of the jumbled A’s, T’s, G’s, and C’s (adenine, thymine, cytosine, and guanine) that make up its genes. This effort will see scientists reporting important data gleaned from the genome, such as the role of specific genes, the identification of genes that are linked to diseases, and a better understanding of the timing of gene expression. These efforts will require new or improved assay systems, automated processing equipment, computer software, and advances in computational biology.
Of considerable importance to understanding the human genome are the continuing efforts to sequence the genomes of other creatures, including the mouse. Many genes are conserved; that is, the same gene exists in many species, and the functions of certain of these genes have been discovered in species other than humans. By matching, say, the mouse and human genomes, a gene with a known function in the mouse can be pinpointed in humans. During the next 7 years, progress along the frontlines of human genomics should identify most genes associated with various diseases and indicate how a malfunctioning gene relates to the ailment, which would open new windows to therapy.
Genomics will change many current approaches in medicine and related health sciences. One area likely to see radical change is toxicology. The field has traditionally relied on animals—such as rats, mice, rabbits, dogs—to gauge the toxicity of substances. But genomics research has led to an emerging field known as toxicogenomics. In it, researchers apply a suspected toxin to DNA placed on glass to observe any effects it may have on gene expression.
Genes carry the codes for proteins, which do the actual work within an organism. The genomic revolution has ushered in the age of proteomics, an even more difficult challenge in which the goal is nothing less than understanding the makeup, function, and interactions of the body’s cellular proteins. Indeed, proteomics poses a more complex puzzle than genomics because there are far more proteins than genes. This is so because the messenger RNA that transports the code from a gene for transcription into a protein can be assembled in several ways, and a protein in a cell also can be modified by such processes as phosphorylation and glycosylation.
Proteomics, unlike the traditional study of one protein at a time, seeks to pursue its goals using automated, high-throughput techniques. The development