[intro music] Host – Dan Keller Hello, and welcome to Episode Eighty-one of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m Dan Keller. The science of pharmacogenomics can help identify those genetic variants that are associated with a high or low risk for experiencing an adverse drug reaction or a beneficial therapeutic response. While at the ECTRIMS conference in Barcelona last fall, I spoke with Kaarina Kowalec, a postdoctoral fellow in the Pharmacoepidemiology in MS research group at the University of British Columbia in Vancouver, Canada. We discussed the potential for using pharmacogenomics to optimize the risk/benefit profile in a patient's favor, focusing first on the risk of liver injury with interferon-beta. Interviewer – Dan Keller How are you using pharmacogenomics to assess the risk for interferon-beta-induced liver injury? Interviewee – Kaarina Kowalec Yes, essentially we have two groups of patients. We have ones that have had the drug reaction and then the other ones that have been exposed to the same drug, but do not have the drug reaction. And so we take a saliva sample from all of them, and then we’re basically looking for genetic markers that would either increase or decrease the risk of having the drug reaction. And so by recruiting all these patients, we can use their saliva or their DNA to study whether or not they have some kind of genetic variant or genetic marker that would protect them from having the drug reaction. MSDF Are you doing genome-wide association studies or looking for specific markers? Dr. Kowalec Yes, we’re doing two-fold actually. So the first one is a candidate gene study. So this is looking at a more targeted approach to looking for genes that, based on previous literature, would be likely to be involved in the mechanism of predisposing to liver injury from interferon. So either this is related to interferon the way that it’s degraded in the body, the response towards interferon is regulated, or it can be related to the liver toxicity side. So there’s a lot of other studies that have been done looking at the genetic basis of liver toxicity from, say, flucloxacillin, amoxicillin clavulanates, a few other thrombin inhibitors, and some other cancer therapies. And so from that information we can look at those genes in our cohort. So that’s sort of the targeted approach. And then secondly, we’re doing more of a hypothesis-free type of approach, which is a general genome-wide association study. So this is where you look at every gene in the human genome, so over 20,000 genes. In each gene, you would look at, say, a few different markers within each gene. So we have a total of 1.7 million different markers that we’re looking at to see if they modify the risk of experiencing liver toxicity. MSDF Are you also doing the basic investigation, essentially heat maps, to see what genes are induced or suppressed when interferon is given? Dr. Kowalec No, so that would be, I guess, more microarray or gene expression. I think that would be sort of the next stage. If we could isolate one gene that would be involved, then we could I think then look at the expression of the gene, because, of course, that would be also important to see if interferon has any direct effect on turning on or turning off or reducing or increasing the level of a certain gene. But that would be probably for the next project, I think. MSDF Are you trying to develop a risk assessment model? Dr. Kowalec Yes, so essentially kind of like a test. So it would be once a new patient would come into clinic and, say, they were going to start one of the interferons, we could take their clinical and demographic information, like whether or not they were female, whether or not they were within a certain age group, whether or not they drinked, whether or not they took different co