The prediction and discovery of segregation distortion genes looks more important to me than PE, given that PE looks like nothing new or important at all.
The discovery of transposible elements may have happened in 1950 but the implications for population genetics had still not been examined the last time I looked. They have the potential to revise most of the early genetics conclusions. For example, Fisher and Wright had an argument about evolution of dominance which Wright won. It would take longer than the lifetime of an average species to select for a gene that affected the dominance of another gene, given the assumptions of the time. But that was assuming genes that were evolved to affect dominance that arose in place by mutation and natural selection. A transposon that can move around in the genome, causing the block of DNA it inserts into to become dominant or recessive, could be selected very fast. A copy that inserts in a gene that is favorably selected and makes it dominant would increase in frequency with the gene it improved. And a copy that happened to insert into a gene that is deleterious and makes it recessive will at least survive much longer than it would otherwise, maybe long enough to transpose copies elsewhere. If they switch between making their genes dominant and recessive at a fairly low rate—say 10^-4 -- they won’t be subject to much unfavorable selection when that’s in the wrong direction but they’ll be nicely selected when it works.
Many of the assumptions of the classical theoretical geneticists are wrong given the existence of transposible elements. The whole thing has to be thought out fresh.
The prediction and discovery of segregation distortion genes looks more important to me than PE, given that PE looks like nothing new or important at all.
The discovery of transposible elements may have happened in 1950 but the implications for population genetics had still not been examined the last time I looked. They have the potential to revise most of the early genetics conclusions. For example, Fisher and Wright had an argument about evolution of dominance which Wright won. It would take longer than the lifetime of an average species to select for a gene that affected the dominance of another gene, given the assumptions of the time. But that was assuming genes that were evolved to affect dominance that arose in place by mutation and natural selection. A transposon that can move around in the genome, causing the block of DNA it inserts into to become dominant or recessive, could be selected very fast. A copy that inserts in a gene that is favorably selected and makes it dominant would increase in frequency with the gene it improved. And a copy that happened to insert into a gene that is deleterious and makes it recessive will at least survive much longer than it would otherwise, maybe long enough to transpose copies elsewhere. If they switch between making their genes dominant and recessive at a fairly low rate—say 10^-4 -- they won’t be subject to much unfavorable selection when that’s in the wrong direction but they’ll be nicely selected when it works.
Many of the assumptions of the classical theoretical geneticists are wrong given the existence of transposible elements. The whole thing has to be thought out fresh.