Comments on: Sbling Razib and Yudkowsky do bloggingheads.tv

By: razib

razib — Sat, 06 Feb 2010 23:24:29 +0000

oh, and i realized a good way to clarify my psychology. i was using “mutation” as if it was a term like “allele” or “locus,” an evolutionary genetic abstraction. i wasn’t using it like “SNP” or “gene,” which are concrete entities (gene can also be abstract).

anyway, in the future i’m going to avoid using mutation broadly unless i make the abstract context explicit.

By: razib

razib — Sat, 06 Feb 2010 23:08:42 +0000

yeah. i regularly think of ploidy as a form of mutation. i.e., i refer to polyploid apples as “mutants.” i do think in most peoples’ minds though mutation doesn’t refer to such massive genomic events, so i have to be careful in the future. but yes, for the record, i simply referred to trisomy 21 as a mutation. probably has to do with my orientation more toward evolutionary than molecular genetics; the structure of how changes occur are usually less salient to me than the change (also, one of my profs is a developmental geneticist who would talk about ploidy events as mutations).

By: DK

DK — Sat, 06 Feb 2010 22:38:46 +0000

@Razib:

Although this may sound like splitting hairs, since in overwhelming majority of cases Down syndrome is a simple trisomy (not a “mess up of the smallest chromosome” or large scale chromosomal rearrangements), it is indeed incorrect to refer to it as mutation. Unless mutation is defined to include aneuploidy which I don’t think it is in most people minds; or unless a reference is made specifically to a small minority of Down cases.

By: razib

razib — Sat, 06 Feb 2010 22:23:45 +0000

dk is right. the main issue of course is that if you select ancestrally informative genes you don’t need to type as many. but the structure/frappe plots which have tens of thousands of snps show the same geographic variation.

By: razib

razib — Sat, 06 Feb 2010 22:18:17 +0000

i meant mutation in a general broad sense. since i referred to it being a mess up of the smallest chromosome, i thought that was pretty obvious, but fine enough if you want to jump on me about that. i’d rather not get into moronic semantic arguments (e.g., “what is a gene”), but i did just double check and large scale chromosomal rearrangements are classified as types of mutations by some sources. the main issue is that since i was talking about SNPs the whole time i probably should have clarified. but 60 minutes isn’t that much time….

By: DK

DK — Sat, 06 Feb 2010 21:23:58 +0000

So, if you select genes to id race by presumed categories, then test to see if your presumed categories are identifiable using those genes, THEY ARE!!!!11!!

Yes. But you don’t need to select any genes. Pick genes at random – just pick many of them and the racial categories will be easily identifiable.

@Callie: Razib is a professional blogger. He does not need to know genetics at depth.

By: Callie

Callie — Sat, 06 Feb 2010 11:31:27 +0000

I thought Razib knew a lot more about genetics than he demonstrates here.

Down syndrome is not a mutation, dude, it’s a chromosomal disjunction. Lucky for him his thesis on selection reducing DS through eugenics in France derailed before he choked on it.

By: Greg Laden

Greg Laden — Sat, 06 Feb 2010 11:10:07 +0000

So, if you select genes to id race by presumed categories, then test to see if your presumed categories are identifiable using those genes, THEY ARE!!!!11!!