61.   Jaenisch said that extreme obesity has developed in many cloned animals, including Dolly, the first mammal cloned from an adult cell.

62.   Opponents said the stem cells had little more value than adult cells, and threatened to stop the effort.

63.   Scientists hope to someday manipulate stem cells into adult cells of their choosing.

64.   Similarly, in the Australian method, the donated adult cell was chemically stimulated to jettison one of its sets of chromosomes before it was joined with an egg.

65.   Some scientists doubt, however, that it will be as easy to direct the growth of adult cells as it is to manipulate embryonic stem cells.

66.   Stem cells are cells that have yet to develop into specialized adult cells or organs, such as blood, nerve or muscle tissue.

67.   The idea is to grow the stem cells into adult cells, which can then be kept ageless and dividing through telomerase, an enzyme that controls cell aging.

68.   The offspring would have only the genes from the adult cell.

69.   Dolly the Sheep, the first mammal to be cloned from an adult cell, was reported last month to have prematurely developed arthritis.

70.   Dolly, the first mammal to be cloned from an adult cell, was being closely monitored by veterinary staff at the centre, Wilmut said.