Dear Sergei,
I would like to study the evolution of a multigene family. I know that this gene evolve under positive selection but I think that given the lineages the selection is not the same.
I would like to test if there is different kind of selection in the different branches of my gene tree. I have done two kind of analysis. The first was to make a test branch DnDs and I have positive result (that’s it the selection is not the same for all branches) with branches evolving under strong positive selection and other evolving under purifying selection. The other analysis consist in estimating a dn and ds value for each branch of the tree, and the value given by this analysis (I think that these values are dn and ds estimations but I am not really sure) are closed to 0. Given the result done by the first analysis I don’t understand anything.
I think that I don’t understand something between these two analysis or in the second but I don’t know what.
So if you could help me...
Thank you in advance for your help
Celine