Teaching molecular medicine within medical education: no time to wait.

Individualization of therapy is not a new concept in medicine, considering it has been central to the practice of medicine since the writings of Hippocrates (1). Under this assumption, medicine is undergoing a very dynamic transformation towards a more predictive, selective and preventive medical practice. During the twentieth century, physicians and researchers moved their attention from the organ to the cells and then to molecules. This new vision was a hallmark in the long and winding road to a more profound understanding of the basis of diseases. At present, a growing body of individual differences, in terms of susceptibility, diagnosis, prognosis and treatment of disease has arisen as a result of this change in approach. We are at the beginning of an era of individualized, molecular and genomic medicine, where diagnosis, prognosis and treatment will be increasingly based on our understanding of human variability (2, 3). Following the success of the Human Genome Project, many kinds of genetic maps are assisting to assign genetic components of disease phenotypes to specific chromosomal regions. For instance, microsatellite maps based on identification of tandem repeats of short nucleotide stretches can map traits or diseases that segregate in large families. Additionally, the number of identified human Single Nucleotide Polymorphisms (SNPs) has grown to more than 10 million; nearly 5 million of these have been validated, but fewer than 700 000 have been assigned population frequency estimates (3–6). The SNP map provides a public resource for defining haplotype variation across the genome and should help researchers to identify multiple genes associated with complex diseases such as cancer, diabetes mellitus, cardiovascular diseases and mental illness. It may assist in identifying novel targets for diagnostic and therapeutic interventions. Some of the segments of the ancestral chromosomes occur as regions of DNA sequences that are shared by multiple individuals. Genetic variants that are near each other tend to be inherited together (ie linked). These regions of linked variants are termed haplotypes. The SNPs are linked to regions coding for disease susceptibility, drug metabolizing enzymes etc so polymorphisms can be used to “map” disease genes. The International HapMap Project was designed to identify common haplotypes in four populations with African, Asian and European ancestry. One of the objectives of this project is to identify the so-called “tag” SNPs that uniquely identify these haplotypes (5). By analyzing an individual’s tag SNPs, researchers will be able to identify the collection of haplotypes in a person’s DNA. The goal is to utilize the haplotype map of the human genome sequence for future genetic association studies of human diseases as well as drug efficacy and safety (7). The description of physiology and illness in molecular terms and the capacity to explain individual susceptibilities to diseases and variations in response to treatments, due to bearing a particular set of genes or haplotypes, have emerged as an important and expanding field that should be increasingly incorporated into undergraduate medical curriculum (8). This is often viewed as a new medical “paradigm”, termed Molecular Medicine or Genomic Medicine, which emphasizes the importance of understanding the role of molecular mechanisms and genetic information in health and disease (9). This new paradigm has become a real challenge which must be addressed as an urgent task in medical academic settings (10–12), particularly in developing countries. The introduction of Molecular Medicine into curricula should be considered not only as simply teaching of the current molecular knowledge in diseases but also as learning activities to integrate both traditional and modern molecular approaches in clinical scenarios (13). This new reform should be considered, not only in undergraduate curricula of medical students but in training programmes for residents and continuing professional development programmes for practising physicians. The development of new skills in future physicians and biomedical researchers will ensure proper diagnosis, more real prognosis evaluation and the best possible treatment for future patients. Because of the revolution in molecular medicine, learning should be considered as a continuous process, we must provide new physicians with lifelong capabilities to understand new developments and assimilate emerging technologies in From: The School of Medicine and Health Sciences Department, Catholic University of Maule, Talca, Chile.