How far are we from genetically-modified people?

Medical researchers are a step closer to fulfilling the promise of preventing disease — not just for living individuals, but for generations to come. Scientists have successfully edited a gene that causes an inherited disease in a human embryo. Will Huntington's, Tay-Sachs, some breast and ovarian cancers — even early-onset Alzheimer's -- disappear for those who have the resources? So far, research is confined to the laboratory, but it's raised hope about eliminating human suffering despite questions about unintended consequences.