Genetic epidemiology of obesity 1

Published on November 30, 2015   33 min

Other Talks in the Series: Obesity: Science, Medicine and Society

So my name is Ruth Loos, I'm a professor of Preventive Medicine at the Icahn School of Medicine at Mount Sinai in New York, and my lecture is on the Genetic Epidemiology of Obesity. And I have structured my lecture in a way that we start in the early years in 1960s, and go in chronological way from the heritability to more recent insights in biology using genetics.
The first period that we cover is the period from the 1960s to the 1990s, and that's when genetic epidemiology became a more formal discipline. At that time, epidemiologists did not have wide access to genetic information, so they relied on relatedness to infer influences of genes.
From the 1960s to the 1990s, the methods that were applied to gain insights in the genetic contribution to obesity were descriptive epidemiology, familial aggregation, heritability studies, and segregation analyses. And I'm going to give you an example for each of these. So first, descriptive epidemiology, there, genetic epidemiologists relied on relatedness within ethnic or within racial groups and it's assumed that some populations are more at risk to develop disease such as obesity than other populations. And a nice example here is given with this picture from the Pima Indians. Descriptive epidemiology is basically searching for patterns in variation in disease risks within racially related individuals or ethnically related individuals and comparing them with other ethnicities or races. It should be emphasized that this type of studies only provide clues to whether genes or environment is involved. It does not really quantify how much genes contribute. So it's mainly hypothesis generating. I'm going to tell you a little bit more about these Pima Indians which is a classical example in the genetic epidemiology of obesity.