In the media there has been several segments on preventing diseases using the DNA or more then two persons. Yet, the only way to truly 100% prevent such diseases is to make sure that no one actually conceives a child with a disease in the first place. And, the only way to do that is to first screen everyone's DNA, sterilize those with any undesirable genes (probably as a child, prior to puberty), and only allow their gametes to be fertilized with medical approval in a lab with government approved modifications.
Remember you don't actually have to have a disease to be a carrier of a disease. What are we going to do have a list of undesirable genes and make sure they don't conflict with any undesirable genes of a potential sexual partner and then get a license to allow to unsterilize ourselves?
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