tag:blogger.com,1999:blog-5506135718533366764.post4123970235278056013..comments2024-03-23T14:27:28.386-04:00Comments on RajLab: Some thoughts on Tomasetti and Vogelstein (and post-publication review)ARhttp://www.blogger.com/profile/13811773097412828786noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-5506135718533366764.post-56383237764813507192015-01-31T19:47:39.465-05:002015-01-31T19:47:39.465-05:00I'm really not an expert on this, but I think ...I'm really not an expert on this, but I think the key point which is sort of tricky to think about is that we normally think about genetic or environmental differences between individuals. In this paper, they are talking about genetic or environmental differences between *tissues*. What is an environmental difference between tissues? Well, some tissues get a lot more exposure than others. That doesn't explain all of it, though, and they give the nice example of the two parts of the GI tract that get cancer at very different rates but have similar environmental exposures. The one that gets much more cancer also has many more divisions, though. Genetic differences is sort of a weird thing to even think about in this context, but the idea is that even a genetic predisposition to a particular cancer does not cause the rate of cancer for a particular tissue to change as much as comparing that tissue to another tissue with a much larger or smaller rate of stem cell divisions. I think it's a relatively unfamiliar comparison to make and was fairly confusing for me–and I'm still probably getting something wrong!ARhttps://www.blogger.com/profile/13811773097412828786noreply@blogger.comtag:blogger.com,1999:blog-5506135718533366764.post-57549692680186546632015-01-31T19:04:52.419-05:002015-01-31T19:04:52.419-05:00"What are the consequences of such a null? To..."What are the consequences of such a null? Tomasetti and Vogelstein frame their discussion around stochastic, environmental and genetic influences on cancer incidence between tissues."<br /><br />Since they're looking at average cancer rates by tissue, doesn't that imply an averaging of differences between individuals (except for a few cases, such as lung cancer, where they compared smokers and non-smokers)? How can they say that their results speak to the effect of genetic and environmental variation (which are differences between individuals) when that variation has been averaged out in their data points?<br /><br /> Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-5506135718533366764.post-1932423565937018452015-01-23T14:12:14.627-05:002015-01-23T14:12:14.627-05:00I think this is spot on, both on the paper and the...I think this is spot on, both on the paper and the twitter responses. I'm fairly new to Twitter, but I'm pretty dismayed at the sometimes pretty vitriolic takedowns of colleagues. Anonymoushttps://www.blogger.com/profile/04974831442484384857noreply@blogger.com