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On Sun 30 Aug Becky Potts wrote; > Thank you Brian! I can accept information from anywhere and I'm glad to do > so. I'd love to hear your views or advice on PD and genetics. > > > > >I have some views on this subject which I would be happy to discuss with > >you if you wish. Meanwhile, best wishes with your Project. > > > Hello Becky, I promised to write with my views on heredity and Parkinsons, so here you are: I have come to believe this rather sweeping picture of what is going on after discussion with two of the neurologists at the nearby (and highly respected) Queen's Medical Centre at Nottingham, UK. The brain cells responsible for the production of Dopamine (in common with lots of other cells) are subject to stress. - Stress in this context means anything which makes it more difficult for the cell to function correctly. If the stress level rises to a level at which the cell cannot function it goes into the process called Apoptosis or Programmed Cell Death. Apoptosis is the way in which all cells in the body are programmed to die, and make way for new cells coming along. (Only in the brain there are NO more cells to fill the gaps because brain cells do not replicate.) The causes of this stress are many and varied, and are expected to number 20 to 30. The causes of this stress are programmed into the DNA code but not in the sense of inherited characteristics, the contents at the 20 to 30 locations are determined by random chance, and it may be that if you are unlucky enough to score badly on say 10 of the sites, then you are at risk of developing PD. This theory has important implications for many aspects of PD. You may have heard from many people who have developed PD after some particularly stressfull experience; the death of a partner; exposure to a toxic chemical; it could be almost anything. In this theory the body absorbs the chemical, and depending on the contents of the cells which are sensitive to that chemical that person may be more or less susceptible. Let us suppose that we have an exposure to some chemical, and develop PD. It would be easy to say "That chemical causes PD", but what about the other hundreds of people who show no sign at all of a toxic reaction? Why did they survive? Under this theory it could be that most of the people are relatively insensitive to this chemical, or maybe most people are equally sensitive, but only one person has enough black marks among the other 20 to 30 sites for this chemical exposure to tip the balance. I imagine that the game of Bingo is known in most countries: the numbers in each column of your card represent the sensitive sites for each person, and the numbers are chosen randomly for each person. Just as in the game, you could say that you lose if you fill any column, or row. It makes quite a good model for you to consider. I am aware that I have complicated the whole subject by several orders of magnitude, but if it was easy then what have all those other epidemiologists been doing all these years. Good luck in your endeavours Regards, -- Brian Collins <[log in to unmask]>