Human Heredity 9th Edition by Michael Cummings

Exercise 3

Success in cloning animals has generated controversy over whether to clone humans in the form of embryos or adults or to treat dis-ease using a method called therapeutic cloning. The goal is to create embryonic stem cells that can be directed to differentiate into functional tissues for use in transplantation. Reprogramming a differentiated adult nucleus will be accomplished by transferring it to an unfertilized egg from which the nucleus has been removed. The nuclear-transplanted eggs are grown to the blastocyst stage. However, instead of transferring the embryos for development, the embryo's stem cells are collected. The stem cells will be grown in the laboratory and, in the presence of growth factors, will differentiate into specialized cells such as liver cells, kidney cells, or insulin-producing cells of the pancreas.
Adding to the ongoing debate about human cloning and embryonic stem-cell research, therapeutic cloning will not use embryos leftover from IVF procedures but requires the creation of an embryo that will be destroyed.
If therapeutic cloning is allowed for the treatment of disease, will we begin a slide down the "slippery slope" toward cloning human beings?