Kindly read about Dr. Dean Ornish who after being inspired by Swami Chitananda is now practicing on reversal of genes.
Mind has the power to do anything, so long as your mind, body and spirit combined as one, demands for it.
It may not alter the genes but it can definitely stop them not to express. Similarly, it can command the islets of langerhans to increase insulin levels, all depending on the state of your mind, body and spirit.
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