Saturday, April 11, 2009

Genetics of domestication   posted by p-ter @ 4/11/2009 07:37:00 PM

Most readers are likely familiar with the classic "taming of the fox" experiment started by Dmitri Belyaev--starting with a wild silver fox, the group was able to quickly breed both a tame and hyper-aggressive line of animals. I was unaware that, concurrently with this experiment, that same group was also performing the same experiment on rats.

Just published is the the first steps in a search for the precise genetic changes underlying the differences between a tame and aggressive line of rats, separated by only 60 generations of breeding. The basic result is that they are able to identify two regions of the genome that very likely carry variation affecting tameness. They are unable to identify particular genes due to the resolution of the study, but one can only assume they're in the process of following this up (since these two lines are only separated by 60 generations, one easy way to search for a causal polymorphism might be to just sequence the two lines--there's likely very few differences between them in the candidate regions).

It was also been noticed, in both the fox and rat experiments, that changes in tameness were associated with changes in pigmentation--in the rat case, the presence of a white patch of fur. This study design allows the authors to determine whether the same locus influencing pigmentation is also involved in tameness. In this case, they're not.