[05:03.26]What exactly so bothers many of us
[05:07.38]about trying to make an exact copy of our genetic selves?
[05:12.92]Or, if we are not bothered, why aren’t we?
[05:17.68]8 We want children who resemble us. Even couples who use donor eggs or donor sperm,
[05:25.33]search catalogs of donors to find people who resemble themselves.
[05:31.13]Several years ago, a poem by Linda Pastan,
[05:35.96]called “To a Daughter Leaving Home,”
[05:39.67]was displayed on the walls of New York subways. It read:
[05:45.52]Is it my own image I love so         In your face?     I lean over your sleep,
[05:53.31]Narcissus over       His clear pool,    ready to fall in ,    to drown for you
[06:00.23]if necessary.
[06:02.58]Yet if we so love ourselves, reflected in our children,
[06:07.99]why is it so terrifying to so many of us to
[06:12.35]think of seeing our exact genetic replicas born again,
[06:17.50]identical twins years younger than we?
[06:21.81]Is it one thing for nature to form us through a genetic lottery,
[06:27.16]and another for us to take complete control, abandoning all thoughts of somehow,
[06:33.80]through the mixing of genes,
[06:36.75]having a child who is like us, but better? Normally, when a man and a woman have a child together,                             
[06:46.02]the child is an uNPRedictable mixture of the two. We recognize that, of course, in the old joke
[06:54.04]in which a beautiful but dumb woman suggests to an ugly but brilliant man that the two have a child.
[07:01.83]Just think of how wonderful the baby would be, the woman says, with my looks and your brains.
[07:09.19]Aha, says the man. But that is the child inherited my looks and your brains?
[07:16.69]9 Cloning brings us face-to-face with what it means to be human and makes us confront both
[07:24.03]the privileges and limitations of life itself. It also forces us to question the powers of science.
[07:32.78]Is there, in fact, knowledge that we do not want? Are there paths we would rather not pursue?
[07:42.08]10 The time is long past when we can speak of the purity of science, divorced from its consequences.
[07:49.89]If any needed reminding that the innocence of scientists was lost long ago,
[07:56.37]they need only recall the comments of J.Robert Oppenheimer,the genius who was a father of the atomic bomb
[08:05.09]and who was transformed in the process from a supremely confident man, ready to follow his scientific curiosity,
[08:14.16]to a humbled and troubled soul, wondering what science had let loose.
[08:20.58]11Before the bomb was made, Oppenheimer said,
[08:24.58]“When you see something that is technically sweet you go ahead and do it.”
[08:30.46]After the bomb was dropped on Hiroshima and Nagasaki, in a chilling speech delivered in 1947, he said:
[08:39.65]“The physicists have known sin; and this is a knowledge which they cannot lose.”
[08:46.79]12 As with the atom bomb, cloning is complex, multi-layered in its threats and its promises.
[08:54.39]It offers the possibility of real scientific advances that can improve our lives and save them. In medicine,
[09:04.05]scientists dream of using cloning to reprogram cells so we can make our own body parts for transplantation.
[09:13.77]Suppose,for example, you needed a bone marrow transplant.
[09:18.97]Some deadly forms of leukemia can be cured completely
[09:24.43]if doctors destroy your own marrow and replace it with healthy marrow from someone else.
[09:31.74]But the marrow must be a close genetic match to your own. If not, it will lash out at you and kill you.
[09:40.47]Bone marrow is the source of the white blood cells of the immune system. If you have someone else’s marrow,
[09:49.01]you’ll make their white blood cells. And if those cells think you are different from them, they will attack.
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