Culture Darwinism horizontal gene transfer Intelligent Design

Question for readers: In a world where horizontal gene transfer is an important force, what becomes of Dawkins’s Selfish Gene?

The selfish gene is an entity driven by an unadmitted teleological force to replicate itself in offspring. But horizontal gene transfer—hardly taken seriously the day before yesterday—features genes that simply end up on a different string. Is a relentless force of selfishness driving them to do that? Or do they just drift and end up on that string?