Soapy Sam
Posts: 659
Joined: Jan. 2012
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| Quote (midwifetoad @ Feb. 20 2015,15:06) | | So when there are no fingerprints, and the door is locked from the inside, goddidit. I think I write a detective novel. I don't think anyone has used that plot. |
There is a problem of sorts, when one looks at an ORFan that is restricted to a single species. How do they change so completely in such a short time frame? But ORFans most likely arise in regions that lack substantial constraint anyway. If the parent sequence was constrained, the ORFan would not get off the ground as a variation on it.
They often seem to arise because transcription/translation signals get wrapped around a random stretch of previously untranslated DNA. Since the original sequence, and probably the new one as well, lack selective constraint, they will just keep diverging at twice the neutral rate. If the new sequence proves beneficial, it's unlikely to be perfect, so directional selection will push it yet more rapidly away from the original sequence. Hey Presto! Genes from nowhere!
Edited by Soapy Sam on Feb. 20 2015,18:19
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SoapySam is a pathetic asswiper. Joe G
BTW, when you make little jabs like “I thought basic logic was one thing UDers could handle,” you come off looking especially silly when you turn out to be wrong. - Barry Arrington
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