Quote:
Originally Posted by carolyn137
By definition somatic mutations occur in the soma, Greek for body, of the DNA of the cells, and are not associated with mutations in the seed DNA.
When I read this earlier you had used the example of a single yellow fruit, re Riesentraube, and saying that seeds from that fruit would not always give yellow fruits,
But they do, and Yellow Riesentraube has been known fo rmany years. Tania didn't have any info for it, so I looked in my SSE YEarbooks and it was first listed in 2000 and remains stable to today.
Casino Chips via the variety Casino has also remained stable as well. Same with Dr. Carolyn Pink.
So if it's a true somatic mutation, a single fruit can be changed, if the mutation is just involved with that one fruit, a single branch can be changed if the mutation is at the base of that branch, and, more difficult to ascertain is if it's a somatic mutation that changes all the fruits on a single plant.
A few years back we thought that a Yellow PRue had appeared, normal is red, but that turned out to be a fluke.
So, seed DNA and somatic DNA mutations are seperate and not related.
Carolyn, who was having a bit of a problem integrating your comments about somatic and seed DNA mutations, when you started talking about hybrids.
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That is correct and that's why I said extremely very very very rare. In fact in higher animals it is impossible. But in plants it is
remotely possible.
A somatic mutation is not in the seed, but instead in one of the many other cells of a plant. In humans for example: A somatic mutation might cause a tumor or a cancer or even a harmless birthmark, but NEVER will that somatic mutation be passed on to the next generation. If it is not a mutation in a reproductive cell it can't be passed on genetically.
Plants are slightly different leaving the
very remote possibility that a somatic mutation could be passed on in exceedingly rare instances. Tom said they wouldn't be passed at all, and he is mostly right. Somatic mutations do not pass on.
The rare exception in plants is when a somatic mutation, lets say in a branch cell, happens to be the cell that divides and produces a new bud which grows a sucker which produces new branches leaves etc.....and eventually a florescence. Then that somatic mutation COULD be passed on. In a human a cell with a somatic mutation on an arm can NEVER form a whole reproductive system. So like all higher animals, somatic mutations are never passed on. In plants a cell with a somatic mutation can in very rare circumstances form a functioning reproductive system and pass that somatic mutation on. Even in plants it is
very rare.
A somatic mutation in a root for example would need to somehow form a new sprout from that root and not only that root, but from that particular cell in that root! Not going to happen often.
More common would be that the somatic mutation will cause the cell to produce a molecule that is taken up by the sap to the rest (or just part) of the plant and can cause a molecular pathway to be activated, maybe even in very rare cases activate a dormant gene, but the mutation, not being in a seed cell, won't be passed on.
So lets take these exceedingly rare exceptions when the possibility of a somatic mutation could be passed on. The cell with the somatic mutation has beaten the odds and the mutation is both useful and the cell by chance happens to be in a growing tip that eventually produces a florescence. You still have the variables of the mutation being a single allele or gene or if it is one of the macro mutations as Tom described.
If it is a micro mutation then the same rules apply for stabilization as apply in traditional breeding work. (ie hybrids) If it is a macro mutation, it possibly could be stable right off (sometimes).
The point is that no matter what, a reputable company will want growouts to prove it. And that is the answer to the OP's question.