Failures in genetic programming may cause death and defects in cloned animals

Defects in a process called gene imprinting may explain why cloned animal embryos often fail to survive or give rise to animals with significant birth defects, a new report has said.

Despite recent success in the cloning of various animals, the use of adult somatic cells as the source of donor nuclei has faced obstacles, among them high rates of abortion, high birth weight among cloned offspring, and an increased likelihood of perinatal death. These shortcomings may be the result of incomplete genetic reprogramming of the donor DNA, …