I read the article Centenarians-The Role of Genetics, by Robert W. Griffith MD : http://www.healthandage.com/professional/Centenarians-The-Role-of-Genetics
As they studied centenarians they decided that lifestyle choices couldn’t be the cause because other people have made similar choices and lived an average life span. They also found it difficult to believe that there were specific long life genes because they didn’t feel that the genes care about longevity they instead care about successful procreation. They did seem to find evidence for what they called the Hayflick phenomenon. This idea encapsulates the idea that cells have a limited number of times they can divide-called cell senescence. They observed younger cell nuclei making more divisions before ceasing than older cell nuclei, supporting this conclusion.
They also found that many of the centenarians they studied had a high functioning sibling that was 90 or older. However, they ran into problems including these siblings in their study since they were not centenarians at the time. They did find, “a photo of a 108-year-old man blowing out the candles on his birthday cake. And right beside him, looking on, was his 103-year-old sister. … We rushed off to recruit the two healthy centenarians for the Sibling Pair Study... As we arranged to meet with him and his sister, he asked whether we might want to meet his other sister, who was 97. We were astonished...Imagine our reaction when they told us it was too bad we hadn't arrived two years earlier when their 101- and 102-year-old sisters were still alive.”
Although we are still unable to determine the specific genes that code for longevity, it is hard to deny that there is some genetic component.
I agree that there seems to be some genetic component with longevity, but I am still curious as to how all of the components fit together. I think it is really interesting that they have moved to sibling studies and would be very interested in their findings. This is especially due to the possibility of environmental similarities if they are all siblings. However, in a sibling study it would be interesting to compare all of the different sets of siblings to each other because surely not all the sibling pairs would have the same environmental aspects. I do think it is hard to deny that longevity runs in families. I also thought the mention of the Hayflick phenomenon was interesting, we've definitely discussed that one in class. I thought it was an interesting article, and I would be interested to see the conclusions of their study.
Fascinating story about the brothers and sisters that you shared! I really like the article you found as well.
ReplyDeleteOne thing I thought was interesting about the article was that when gathering information about the families with several siblings over 100, the researchers realized that their was a strong likelihood of family intermarriage in two of the three families. I found this to be particularly interesting because typically you hear of intermarriage resulting in children with harmful inherited diseases.
ReplyDeleteI think it's interesting that you made the connection to siblings not only sharing genetics, but also environments (at least for about the first 18 years of their lives). I wonder if the siblings would share the long lifespan if they had been separated at birth.
ReplyDeleteNeat story! We will talk about that some more today (talking about epigenetics) and in the future when we talk more about centenarians. Thanks for sharing!
ReplyDeleteYeah, that was a neat article. And I think Heidi raises a good question, because not only did the siblings share similar environments growing up, they probably learned similar habits that they took into their later years that may or may not have contributed to their longevity.
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