In your article, you state that the cloned foal Prometea is a genetic twin of her birth mother which contributed the nuclear DNA. This is not true, as twins have identical nuclear and mitochondrial genes. The cytoplasm of the cloned foal was obtained from a slaughtered horse. The cytoplasm, and therefore the mitochondrial genes, of the foal are from another horse, not the donor of the egg nucleus.
Elizabeth M. Specht Akron, Ohio
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