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Explores the possibility that human life can be created in laboratories engaged in DNA research.
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00:00in ultraviolet light a technician purifies the very essence of life
00:09scientists have acquired profound new abilities they can read the secret code of life and change
00:17its genetic structure the greatest of mysteries may soon be solved we could discover how a human
00:25being develops from a single egg we might even find out what causes life
00:55in a laboratory in San Francisco seven scientists have joined forces on a fantastic quest they are
01:09seeking to penetrate the mysteries of life they can take the stuff of life out of cells
01:19dissect it in a test tube and begin unlocking its deepest secrets this series presents information
01:34based in part on theory and conjecture the producers purpose is to suggest some possible
01:39explanation but not necessarily the only ones to the mysteries we will examine beyond the outer
01:50planets of our solar system space curves off into the vast abyss of the universe scientists believe
01:57our universe exploded into being some 15 billion years ago it formed countless galaxies of a hundred
02:05billion stars on our planet life developed over three billion years it evolved from simple virus like
02:14particles to plants animals and the incredibly complex organism that is man since the dawn of history
02:25people have wondered what is the essence of life several hundred years ago pioneers with microscopes
02:36discovered the basic building block of life the cell cells are the primary unit of life 100 trillion cells
02:44comprise a human being billions of muscle cells skin cells nerve cells and blood cells all working together
02:52to orchestrate our every movement the most remarkable ability of the cell is its capacity to grow and divide
03:00fertilized egg cells begin the process of development that in 21 days will culminate in the birth of baby mice
03:10what marvelous control system governs this miracle of growth what mysterious forces caused the development of a heart
03:21since the early 1950s the science of biology has undergone a revolutionary change scientists have begun to unravel the innermost secrets of the cell
03:35within each cell are tiny structures called chromosomes they contain the information cells need to live and grow
03:45just before cells divide these chromosomes copy themselves exactly they transmit the blueprint of life from generation to generation
03:57the chromosomes are composed of thousands of incredibly small units called genes the genes order the cell to make molecules which are vital to life
04:09genes are made of a molecule called DNA its twisted strands store the genetic information in a simple code DNA is composed of only four chemical units endlessly repeated in various combinations
04:26the magic of DNA is how these simple units determine all the forms of life we know the wonder of DNA is most obvious in the phenomenal likeness of identical twins
04:37each girl has inherited precisely the same set of genetic instructions they are what they are because of some hundred thousand genes written in the language of DNA so incredibly precise is this genetic code that Lisa and Ingrid are alike down to their freckles and the tiny nicks on their ears as scientists expand their knowledge of the code of life it is becoming easier to
05:07to change life to change life to alter its genetic structure chromosomes genes and DNA are tiny chunks of matter they can be engineered cut up and rearranged in endless combinations the technology can be developed some of it already exists
05:23in dealing with human life biologists are much more limited once a child is born its genetic structure is fixed unchangeable if the genetic instructions are faulty
05:36little can be done the result could be a crippling disease it is possible however to detect some genetic defects during pregnancy because her risk increases with age this woman has decided to have a test an obstetrician withdraws some fluid from the sac surrounding the growing fetus
06:00in the fluid are a few of its cells the cells the cells are added to a nutrient broth in which they can live and grow
06:07placed in an incubator the cells multiply until there are enough for the test a technician searches for cells in which the chromosomes are easy to see she checks the size and size of the cell
06:28she checks the size and shape of each one in this case the chromosomes looked perfectly normal
06:35however when the genetic structure of healthy cells is damaged the result may be cancer
06:43normal genes switch off while malignant genes switch on
06:50renegade cells grow out of control they invade the tissues around them and form tumors
06:58the fast-growing tumor on this mouse's back will rapidly kill it
07:04at the Lawrence Livermore lab some of the tumor cells are removed their DNA is stained
07:11with a special dye when the blue laser beam hits the DNA it causes tiny flashes of light
07:18these flashes are detected electronically their pattern is typical of cancer cells
07:23which have more DNA than normal cells the scientists have another extremely sensitive way to check chromosomes
07:34an electronic scanner hooked up to a computer forms pictures which show the precise amount of DNA in each chromosome
07:42so exact is this system that it tells the difference between chromosomes inherited from the mother
07:51and those from the father
07:54with such computerized technology we begin our journey into advanced genetic research
08:00to prove the mysteries of cell division a powerful laser beam is used to perform surgery on cells and chromosomes
08:11Dr. Michael Burns of the University of California at Irvine has developed this remarkable technique of genetic engineering
08:19a lens focuses the laser light into a tiny beam which cuts through cells like a microscopic scalpel
08:26the beam is so precise that it can be aimed at individual chromosomes and even used to snip off pieces containing a few genes
08:42Dr. Burns finds two chromosomes and hits them with the laser
08:49the cell is not destroyed it continues to divide but the chromosomes hit by the laser are expelled
09:03their messages will not be passed on to other cells what comes next is another amazing feat of microsurgery
09:10the manipulation of cells a thousandth of an inch across
09:15carefully all the cells around the one hit by the laser are scraped away
09:20a nutrient fluid is added so that the single cell remaining can reproduce itself
09:29over the next few weeks that single cell will divide into a colony of identical cells
09:35mysteriously the destroyed chromosome is replaced by the remaining ones thus restoring normal chromosome number to the cells
09:50other biologists have developed more precise techniques of genetic engineering
09:54they can chop DNA molecules into pieces without destroying the molecules ability to play the game of life
10:02if they could link up these pieces in the right combination they might solve the mysteries of the gene
10:09if they could insert bits of DNA into living cells they could create forms of life with new genetic structures
10:21their testing ground has been a tiny bacterium called E. coli
10:28it lives in the human intestine where its functions are largely unknown
10:33the molecular biologists have found a way to splice genes from animals and plants into E. coli's well known genetic structure
10:40so cooperative are these bacteria that they willingly accept the foreign DNA and copy it as if it were their own
10:57a revolution in medicine may be on the horizon
11:03already gene splicing is being used to attack the human disease of diabetes
11:10scientists long time dream of genetic engineering is at hand
11:14they are getting closer to the secrets of life
11:20since the discovery of DNA biologists have been manipulating the very essence of life
11:35today they can take DNA out of one cell and insert it into another
11:40they can even mix the genes of different species
11:43by transplanting animal genes into bacteria
11:46they hope to find out how these genes work and are controlled
11:55the process begins when a strain of bacteria is given an ample supply of food and gently shaken
12:01in less than 24 hours each bacterium can multiply 100 billion fold
12:16after the bacteria are harvested a detergent bursts open their cell walls and sticky DNA strands spill out
12:22most of the DNA clumps together in a distillery tangle
12:37but nearby are tiny loops of DNA called plasmids
12:43they are the key to the new technology of gene splicing
12:50they will accept any genes the biologists can stitch into them
12:54a fast spinning centrifuge separates the plasmids from the rest of the DNA
13:02a fast spinning centrifuge separates the plasmids from the rest of the DNA
13:09under ultraviolet light a fluorescent dye makes the plasmid band visible
13:16carefully the precious plasmids are removed
13:21now come the most crucial steps
13:28in this simulation a special enzyme is added to the plasmids
13:32like a pair of microscopic scissors it snips open their DNA molecules at specific points
13:39other snipped genes can now be added to the open plasmid loops
13:44the foreign DNA joins the plasmids creating a new DNA molecule
13:51the resulting loops called recombinant DNA combine animal genes with bacterial genes
13:58they will be reinserted into other bacteria giving those bacteria new genes
14:05when the bacteria multiply their new blueprint is copied over and over
14:12thus science can make life forms with new combinations of genes
14:19Dr. William Rutter is chairman of the biochemistry department at the University of California San Francisco
14:28the possibilities for recombinant DNA technology are simply enormous
14:33not only are we going to revolutionize the understanding of the human genome
14:39and for genetics in general but we will have profound effects on many aspects of biomedical science
14:46over 40 million people are affected by the genetic disease called diabetes
14:52in the United States alone more than a million people inject insulin each day in order to stay alive
14:59this insulin comes from the pancreas gland of animals
15:02it is in short supply worldwide and often produces undesirable side effects
15:09my colleagues and I have been studying the expression of the insulin gene in the embryonic rat pancreas for several years
15:16and one day I attended a faculty meeting in which Herbert Boyer and Howard Goodman
15:20were discussing their work on recombinant DNA
15:23this excited me a great deal and I cornered these two individuals after the meeting and said
15:28Herb and Howard we must we just must clone the insulin gene
15:32what the scientists proposed to do would have seemed impossible ten years ago
15:37of the thousands of genes in each cell of the laboratory rat
15:41they wanted to isolate the single gene that makes insulin in the rat's pancreas gland
15:47then they would transplant this gene into bacteria hoping to create a microbe
15:53with the insulin producing ability of a mammal
16:05if they could make it work for the insulin gene
16:08it might become possible to make dozens of important hormones and drugs
16:12a group of scientists at the university began to collaborate on the experiments
16:21so we obtained the insulin producing cells from several hundred rats
16:28and extracted from them the chemicals from which we could get the DNA
16:31Axel Ulrich took this material inserted it into a plasmid
16:38and placed the plasmid into a strain of bacteria that could only grow in the laboratory
16:42these steps of the experiment were carried out under strict conditions of containment
16:49howard goodman is professor of biochemistry at the university of California San Francisco
16:56we had been working on the cloning of rat insulin for about a year
17:00we had many technical difficulties and we began to overcome them
17:04but it wasn't until the moment I saw this film
17:07which was the analysis of the gene that we had cloned
17:10that we really knew we had the rat insulin gene in the bacterium
17:14the next step is to show that the genes which we have transplanted to the bacterium
17:20can actually work and produce insulin
17:22we'll then try to insert human genes into bacteria instead of the rat genes
17:27if we can get these genes to work
17:29this would provide a virtually inexhaustible supply of human insulin
17:32much better than animal insulin since it would have no undesirable side effects
17:36eventually in a generation or so we might be able to do something which is really fantastic
17:43it might be possible to rejuvenate the defective cells in the diabetics
17:48so that they would produce insulin in a normal fashion
17:51thus the disease would be cured
17:53in the future bacteria modified with recombinant DNA may be grown in industrial amounts
18:08the bacteria could produce hormones like insulin and other important drugs
18:14new fast growing strains of bacteria or algae could be used in vast amounts as animal feed or fuel
18:21or fuel
18:28a whole new technology will be needed to pick the desired bacteria
18:34automation will be used to inoculate incubate and photograph bacteria
18:50the system produces thousands of photographs under computer control
19:03these could be used to select the most productive bacteria for industrial use
19:08breakthroughs in genetic engineering may open up a whole new realm of biology
19:15until recently it has been very difficult to identify specific genes on animal chromosomes
19:22but with new techniques of gene splicing scientists have begun to map the uncharted terrain of the chromosome
19:30Stanford University biologists have made a remarkable photograph of fruit fly chromosomes
19:42while trying to locate a certain gene on one chromosome
19:45they found to their surprise that the genes DNA code was repeated dozens of times
19:51to explain this important finding the scientists came up with a new idea
19:58just as each letter of the alphabet is found in many different words
20:02each gene copy may play a different role in the life process of the fly
20:06biologists are now busy testing this idea
20:12it could be the key to the miracle of growth
20:15helping explain how a human being develops from a fertilized egg
20:19the new molecular biology is leading to cures for genetic diseases
20:29it may enable us to engineer our own genes and influence our destiny
20:35it might even lead to complete knowledge of the secret of life
20:42but is it possible to explain life in terms of chemicals and molecules
20:47or are there profound mysteries beyond the gene
20:54while raising hopes of great advances in medicine and biology
21:01recombinant DNA research has also created a major controversy
21:08tinkering with the stuff of life is not without its risks
21:11some people are afraid that a bit of DNA spliced into a harmless bacterium
21:16could create a deadly germ
21:18others fear that mixing genes from different species
21:21could have unpredictable effects on evolution
21:24government agencies have enacted strict controls for recombinant DNA research
21:29most scientists say that if these guidelines are followed
21:32genetic engineering is not dangerous
21:36with today's technology we can only add a few foreign genes to bacteria
21:43but a hundred years from now
21:46we may be able to mold genetic structure as freely as a sculptor shapes clay
21:50the question is will we be ready for the power to change life
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