“What’s Up with Epigenetics?” outlined the basic idea of how things come into the body and cause chemical reactions that switch genes on and off. The activity or dormancy of the relevant genes affects every system. Along with the knowledge of these mechanisms came first the suspicion, and then what looks very much like proof, that some epigenetic changes can be passed along to children and even grandchildren.
It would be nice to think that we all start out as a blank slate, ready to be shaped by our own life experiences. But that’s not entirely true… The truth is there’s a probability that whatever our parents experienced , like smoking or perhaps a bad pollen season, could affect us. How this happens is not fully understood, but new research is uncovering more about how these epigenetic modifications are maintained.
As a specific example, an important study showed that the mothers who smoke during pregnancy tend to have children troubled by allergies, and these children also show changes in DNA methylation — changes that carry over to their own allergic children. Ancient scriptures spoke of a deity who would punish the guilty “even unto the third and fourth generation.” All those years ago, some things could be observed without microscopes.
With over 20,000 genes, each of which might be either silent or expressed, the number of possible combinations is astronomical. The “basic explanation” page at WhatIsEpigenetics.com elaborates:
The possible permutations are enormous! But if we could map every single cause and effect of the different combinations, and if we could reverse the gene’s state to keep the good while eliminating the bad […] then we could theoretically cure cancer, slow aging, stop obesity, and so much more.
Researchers are talking about ending disorders associated with mental retardation, neuropsychiatric problems and various pediatric disorders, and even finally putting a dent in some types of cancer. Under particular scrutiny is the vast panoply of autoimmune diseases.
At the same time, the scientists in this field also study a contagion that unquestionably comes from the outside. Influenza is still a major killer. The crafty flu virus tricks the immune system by manufacturing a protein that is mistaken by genes for something else.
This whole epigenetics thing is taken very seriously by endocrinology researchers. In fact, the prevalence of type 2 diabetes was the tipoff — the clue that something weird was going on. Science writer Bill Sullivan describes how suspicions were provoked by the rapid increase of diabetes throughout the world, too rapid to be accounted for by genetic mutation.
Investigation showed that rather than altering the DNA the epigenetic mechanism did the harm through gene activation. Even more frightening, it was discovered that “the RNA transcripts present in the oocytes and sperm may contribute to programming the zygote’s DNA.”
Sullivan puts it like this:
In addition to inheriting a genetic risk factor in the classic sense, children can also inherit non-genetic information. If you consider DNA to be a “book of life”, the book handed down to the child is not necessarily a pristine copy — some passages may be highlighted, a page or two may be missing, or notes may be scribbled in the margins.
Your responses and feedback are welcome!
Source: “Could Epigenetics Explain the Origins of Allergic Disease?,” WhatIsEpigenetics.com, 03/24/15
Source: “A Super Brief and Basic Explanation of Epigenetics for Total Beginners,” WhatIsEpigenetics.com, 07/30/13
Source: “Epigenetics: Feeding the Obesity and Diabetes Epidemic?,” WhatIsEpigenetics.com, 03/21/16
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