Clones from aged cows have normal pregnancies and calving


FOR MORE INFORMATION:
David Bauman   Tel: 860-486-5627 (office)
E-mail: david.bauman@uconn.edu


June 5, 2001

STORRS, Conn. -  Researchers from the University of Connecticut
announced today that a Holstein heifer named "Daisy", cloned two years
ago from an aged cow, has given normal birth to a 90-pound male calf.

The calf named "Norm" was born at the UConn Kellog Dairy Center at 9
A.M. on Sunday, June 3, 2001, said Dr. Xiangzhong (Jerry) Yang, head of
UConn's Transgenic Animal Facility. "Daisy gave birth without any
assistance," Yang said. "Both the Mom and calf are doing fine."

Scientists have previously reported on cloned cows giving normal births
in Japan, but these clones were made from young donor cows or from
unknown slaughterhouse animals.

What makes Norm's birth special, researchers say, is that Daisy was
cloned from an aged animal (passed menopause). The fact that Daisy can
reproduce normally demonstrates that the cloning process can reverse the
physiological age process, similar to conventional reproduction.

Ever since researchers in Scotland electrified the world by cloning
"Dolly" the sheep, scientists were concerned that cloned animals might
prematurely age, reflecting the age of the DNA of the animals from which
they were cloned. Recently, Yang's team reported in the journal Nature
Genetics that all clones have normal cells with regard to telomeres
(lengths of DNA on the ends of chromosomes), indistinguishable from
calves produced from conventional reproduction. Their results showed
that cloned calves do not have cells that are unnaturally old and do not
inherit the cellular genetic age of their donor.  Similar results have
been found by the Worcester, Mass.-based company Advanced Cell
Technology in cattle, and by the Rockefeller University in mice.

"Although it might be anticipated that clones from aged animals may have
normal reproductive capacity as those cloned from young animals, the
normal birth of 'Norm' and several other normal pregnancies from aged
clones here at UConn provides evidence that when you clone from an aged
individual, you do not get an aged copy," Yang said.

Despite other problems reported associated with cloning, including high
rates of abortions and neonatal death, Yang said that research has shown
that cloned animals, once they have passed the first few critical days
after birth, can live and reproduce normally as conventionally
reproduced animals. Yang notes that his UConn research team and their
Japanese collaborators have produced several dozens of clones from adult
cattle, male or female.  Almost all of the surviving clones are
appearing as normal as other calves.

"These findings are significant because of their important medical
implications," added Yang. He suggests that Norm's successful birth
moves science a bit closer to the promise of "therapeutic cloning," in
which human's own cells would be harvested for tissues that could treat
diseases such as diabetes or Parkinson's.

"Therapeutic cloning is aimed to convert skin cells or other somatic
(body) cells from diseased individuals to embryonic stem cells, which
may then be differentiated into any needed cell or tissue types for
therapy," Yang said. "Obviously demonstration that clones from aged
animals can develop and reproduce normally is important  because when
therapeutic cloning is eventually applicable to human therapy, older
individuals are likely to be the intended beneficiaries for treatment."

"Norm's birth is also significant for agriculture and saving endangered
species," Yang added. "Proven valuable animals are desired to be cloned
and normal reproductions of the clones are of course desired."

Daisy was cloned from a 13-year-old high-merit cow named "Aspen," and
was born on July 7, 1999 at UConn. Two other Holstein heifers - named
"Betty" and "Cathy" - also cloned from Aspen, are due to calve soon,
Yang said.

Daisy is the fourth live-clone produced at UConn. Her other sister - the
now famous "Amy" - was born on June10, 1999 to become the first clone of
an adult large animal in North America. A total of  ten clones have been
produced from Aspen, the aged cow.  Four of the ten - Amy, Betty, Cathy
and Daisy - are still alive.

Aspen, who also is still alive, is now nearly 15-years of age and has
long passed her calf-bearing age. Aspen had a high milking record,
producing approximately 35,000 pounds of milk per year. It is yet to be
determined whether her clones will have the same high-milk production
ability.



For more information contact:

Dr. Jerry Yang
Professor and head of the Transgenic Animal Facility, University of
Connecticut.
Tel: 860-486-2406
Cell: 208-9078
e-mail: jyang@canr.uconn.edu

Dr. Maneesh Taneja
Research Associate, Transgenic Animal Facility, University of
Connecticut
Tel: 860-486-1175
e-mail: maneesh.taneja@uconn.edu

Additional comments may be requested from the following external
experts:

Dr. Robert H. Foote
Professor Emeritus, Department of Animal Science; Cornell University;
Ithaca, NY 14853
Tel: 607-255-2050; e-mail: dgb1@cornell.edu

Dr. Thomas Wagner
Professor of Molecular Biology; Director of Oncology Research,
Greenville Hospital System,
Clemson University; Greenville, SC 29605-5601
Tel: 864-455-1565; e-mail: thomaswagner@home.com

Dr. Gary Anderson
Professor and head, Department of Animal Science; University of
California at Davis
Davis, CA 95616-8521
Tel: 530-752-1682; e-mail: gbanderson@ucdavis.edu

Dr. Caird Rexroad
Senior Scientist, USDA, ARS; Beltsville, MD 20705
Tel: 301-504-7050; e-mail: Cer@ars.usda.gov

Dr. Kenneth L. White
Professor, Department of ADVS/Biotechnology Center; Utah State
University
Logan, UT 84322-4815
Tel: 801-797-2149; e-mail: kwhite@cc.usu.edu

Dr. James Robl
President, Hematech Worcester Molecular Biology Lab; Biotech IV;
Worcester, MA 01605
Tel: 508-792-0682; e-mail: jrobl@hematech.com

Dr. Jose Cibelli
Vice President, Advanced Cell Technology; Worcester, MA 01605
Tel: 508-756-1212; e-mail: jcibelli@advancedcell.com

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