SCIENTISTS IN THE UNITED STATES HAVE MADE HUMAN CHROMOSOMES. THEY SAY THESE ARTIFICIAL HUMAN CHROMOSOMES WORK LIKE NATURAL ONES. SOMEDAY DOCTORS MIGHT USE THEM TO REPLACE GENES THAT CAUSE DISEASE.23-Apr-97CHROMOSOMES ARE THE STRUCTURES INSIDE CELLS THAT CARRY THE GENES THAT MAKE EACH PERSON DIFFERENT.
HUNTINGTON WILLARD HELPED LEAD A TEAM AT CASE WESTERN RESERVE UNIVERSITY IN CLEVELAND, OHIO. THE SCIENTISTS MIXED NATURAL AND ARTIFICIAL HUMAN GENETIC MATERIAL. THEY DID THIS BY PUTTING SOME CHEMICALS INTO HUMAN CELLS IN A LABORATORY. THE CHEMICALS ARE NEEDED TO MAKE COPIES OF CHROMOSOMES WHEN CELLS DIVIDE. THE MIXTURE FORMED INTO CHROMOSOMES.
MISTER WILLARD SAYS THE GOAL WAS "TO MAKE THE SMALLEST POSSIBLE WORKING VERSION OF A HUMAN CHROMOSOME." THE RESULT WAS A CHROMOSOME ABOUT ONE-TENTH AS BIG AS A NORMAL CHROMOSOME IN THE BODY. THEY PUT THE SMALL VERSION OF A CHROMOSOME INTO CELLS. MISTER WILLARD SAYS THEY FOUND IT COULD WORK AS WELL AS A NORMAL CHROMOSOME.
THE EXPERIMENT COULD LEAD TO NEW FORMS OF GENE THERAPY. THIS TREATMENT PUTS GENES INTO THE BODY TO FIX ONES THAT DO NOT WORK RIGHT. IT ALSO CAN REPLACE MISSING GENES. RESEARCHERS NOW TRY TO TREAT DISORDERS LIKE CYSTIC FIBROSIS BY LINKING HEALTHY VERSIONS OF GENES TO CHEMICAL TRANSPORTS. THESE TRANSPORTS ARE CALLED VECTORS. THEY ARE INJECTED INTO THE BODY OR BREATHED IN BY THE NOSE. THEY ARE SUPPOSED TO CARRY THE GENES TO THE CORRECT CHROMOSOMES. USUALLY THE VECTOR IS A COMMON COLD VIRUS THAT SCIENTISTS HAVE CHANGED SO IT DOES NOT CAUSE INFECTION.
YET GENE THERAPY HAS A LOW SUCCESS RATE. NO ONE CAN BE SURE THE GENES WILL BE EFFECTIVE, OR WILL EVEN REACH THE CORRECT CHROMOSOME. MISTER WILLARD SEES ARTIFICIAL CHROMOSOMES AS BETTER VECTORS TO GET GENES INTO CELLS.
GENETICIST HUNTINGTON WILLARD SAYS THAT NOW THE TECHNOLOGY IS DESIGNED TO TREAT DISORDERS CAUSED BY A SINGLE GENE. HE DISMISSES CONCERNS ABOUT OTHER POSSIBLE USES, SUCH AS ADDING GENES TO MAKE PEOPLE MORE INTELLIGENT. HE SAYS ADDING GENES TO CELLS RAISES MEDICAL RISKS.
THE TEAM AT CASE WESTERN RESERVE UNIVERSITY WORKED WITH A BIOTECHNOLOGY COMPANY IN CLEVELAND CALLED ATHERSYS. THE COMPANY HOPES TO SELL ARTIFICIAL CHROMOSOMES. HOWEVER, IT SAYS TESTS ON ANIMALS CANNOT BEGIN UNTIL MORE WORK IS DONE TO IMPROVE THE TECHNOLOGY.