Proteomics and disease: opportunities and challenges.

Since the human genome was sequenced, there has been intense activity to understand the function of the 30,000 identified genes; attention has now turned to the products of genes--proteins. Proteomics is the large-scale study of the structure and function of proteins; it includes the rapidly evolving field of disease proteomics, which aims to identify proteins involved in human disease and to understand how their expression, structure and function cause illness. Proteomics has identified proteins that offer promise as diagnostic or prognostic markers, or as therapeutic targets in a range of illnesses, including cancer, immune rejection after transplantation, and infectious diseases such as tuberculosis and malaria; it has the potential to allow patient-tailored therapy. Some major challenges remain, both technical (eg, detecting "low-abundance" proteins, and maintaining sample stability) and in data management (eg, correlating changes in proteins with disease processes).