Linkage and association studies
Professor James Potash describes the difference between linkage and association studies, which are two ways of locating candidate genes. These are discussed in reference to bipolar disorder,
There are two major approaches to looking for candidate genes in bipolar disorder; the one that has been focused on the most is the gene-mapping approach, which is a hypothesis-free approach. Part of the reason thatâ€™s so attractive is because there has been so little that weâ€™ve understood about the pathophysiology of the illness, of the way the illness unfolds in the brain, that weâ€™ve thought that if we can from a hypothesis-free approach go directly to the gene it would be a huge advance. Linkage was the original way to go about that; that was a very low resolution way to screen the genome, looking for regions where there might be bipolar disorder genes. We are now at a much higher resolution approach thatâ€™s referred to as whole genome association, where you can look at seven hundred thousand to a million different places in the genome all at once; thatâ€™s the state of the art right now.
candidate genes, linkage, association, gene mapping, genome, bipolar disorder, james, potash
An overview of bipolar disorder-related content on Genes to Cognition Online.
Doctor Anil Malhotra discusses the search for genes in both bipolar disorder and schizophrenia, both of which are in their infancy.
An overview of depression-related content on Genes to Cognition Online.
Professor James Potash describes how endophenotypes are used to study bipolar disorder. Endophenotypes are essentially subtypes of larger symptoms.
Professor James Potash discusses two hypotheses on how lithium, which has been successfully used to treat bipolar disorder for many years, may affect the brain.
Professor James Potash describes how the diathesis-stress model can be used to understand interactions between genes and the environment. He refers specifically to bipolar disorder.
Locate a disease gene by screening for markers linked to the gene.
While many genes and loci have subsequently been found to associate with bipolar disorder, none have been unambiguously identified as causal.
Professor Allen Moore describes the differences between linkage and association studies, which are low- and high-resolution techniques used to search for candidate genes.
Doctor Anil Malhotra compares (older) linkage and (more modern) association techniques for identifying candidate genes for disorders.