Taillessness in a Cloned Cow is Not Genetically Transmitted.

Somatic cell nuclear transfer (SCNT), commonly referred to as cloning, results in the generation of offspring that, except for mitochondrial DNA, are genetically identical to the nuclear donor. We previously used a genetically modified bovine cell line as the donor for SCNT and obtained a calf, named Daisy, that was born without a tail. To determine whether the missing tail was a result of the genetic modification, we performed recloning experiments by using either cells from a sacrificed pregnancy of a second clone (Daisy's "twin" clone) or cells from tailless Daisy as donors for SCNT.