tag:blogger.com,1999:blog-7447544468792389936.post4555935199136962381..comments2024-02-26T21:18:23.165-08:00Comments on CHIMERAS: Missing heritability: the humble opinion of a mathematicianAnonymoushttp://www.blogger.com/profile/09922888671399516573noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-7447544468792389936.post-50885634173151686962012-09-04T15:39:09.063-07:002012-09-04T15:39:09.063-07:00I was almost tempted not to publish your comment b...I was almost tempted not to publish your comment because, while I welcome all opinions and I am open to discussion, I also appreciate full respect and your language is borderline. SCIENCE IS NOT EASY! MODELING IS NOT EASY! A model is never the full truth and while sophisticated models may encompass more aspects, they may as well not be solvable with the means we have today. So the first approach is the spherical cow and if it works we have a new way of describing the cow. After all, if you sit on the Moon and all you have is a telescope, you might as well see that cows are spherical, if you can see them at all. Then you build a better telescope and surprise, you find out that cows aren't that spherical after all, they have four legs. So now, wiser from your better telescope, you build a new model that encompasses spheres with four legs. Then, in a decade or so you build an even better telescope and realize that cows have necks, too, and mouths, and they ruminate. So now yo build a new model.<br /><br />Get the picture? That's how science works. Models aren't the truth, and simplifications are a necessity. Theories work for as long as they do a good job describing what we see with the tools and means with have at the time. Newton devised a great theory called gravitation. Until Einstein expanded it, it was the best gravitation theory we had. That doesn't mean Newton was stupid.<br /><br />Thanks for your comment. Anonymoushttps://www.blogger.com/profile/09922888671399516573noreply@blogger.comtag:blogger.com,1999:blog-7447544468792389936.post-16283870501964841172012-09-04T15:22:51.961-07:002012-09-04T15:22:51.961-07:00Sorry the strong words, but despite this well done...Sorry the strong words, but despite this well done summary i cannot help but seeing how stupid this discussion on missing heritability is. First geneticists make the deliberate simplifying assumption that genetic factors (now: genomic loci made of DNA) contribute additively (linearly) to a phenotype and do not interact, and they neglect gene-gene interactions. Then they admit it through the backdoor of the vague notion of epistasis which in their world is treated rather as an anomaly to be afraid of. Then, they rediscover the possibility of genetic interactions when their non-interaction models fail. This is in the grander scheme simply utterly poor science of an entire community whose people only talks to each other but not outside that community.<br /><br />This led to the taking for granted an old, idiotic model by an entire community - a view that spread like random genetic drift and got fixated without being tested for its fitness.<br /><br />There exist other communities, such as the fields of nonlinear systems dynamics, complex network theory etc, for which gene-gene interactions are the normal case, and direct linear, additive genotype-phenotype mapping is the rare uninteresting exception.<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7447544468792389936.post-1096405373618798162012-02-02T19:35:40.730-08:002012-02-02T19:35:40.730-08:00here's my reply re plastids, I'm glad you ...here's my reply re plastids, I'm glad you figured it out, because I was going to have to do a little research :) yeah ... plastids are different from mitochondria, what I remember is that they are pigment-containing organelles for "making food". Chloroplasts are the ones we're most familiar with. They have their own genomes, and are thought to have originated through symbiosis, like mitochondria ... or maybe we should call it theft! I just came across the word "kleptoplasts" for plastids that are "stolen" by other organisms ... like sea slugs!! Have you seen the video of a sea slug sucking chloroplasts from algae? <br /><br />http://sbe.umaine.edu/symbio/3Slug/3kleptoplasts.html<br /><br />The plastids are surprisingly stable in the sea slug, and there's a bit of evidence that some genes in the host genome are involved. Wow, that's wild! But then so is a lot of what we're learning these days!<br /><br />Thanks for the great molecular biology posts, I really enjoy hearing about all the new discoveries and thinking.Hollishttps://www.blogger.com/profile/10788942181934895493noreply@blogger.comtag:blogger.com,1999:blog-7447544468792389936.post-71862311078901789152012-02-02T09:59:36.338-08:002012-02-02T09:59:36.338-08:00Thanks, Steve, I agree. Of course, it's always...Thanks, Steve, I agree. Of course, it's always a good practice to start with simpler models first -- we need to make simplifications and approximations, there's no way around it -- but when the simpler models don't work it means it's time to add onto the model.Anonymoushttps://www.blogger.com/profile/09922888671399516573noreply@blogger.comtag:blogger.com,1999:blog-7447544468792389936.post-45872663878331002992012-02-02T09:15:53.134-08:002012-02-02T09:15:53.134-08:00It makes a great deal of sense that many, many fac...It makes a great deal of sense that many, many factors influence a particular set of genetic triggers.Steve Halterhttps://www.blogger.com/profile/03160423930602205230noreply@blogger.com