What is cloning?
Cloning is an assisted reproductive technology that allows livestock breeders to create identical twins of their best animals. This breeding technique does not change the genetic make-up of the animal. The most common cloning procedure today is known as somatic cell nuclear transfer (SCNT), which makes it possible to produce many animals from a single donor. SCNT involves transferring the genetic information from one animal into an empty oocyte, or egg. This process results in an embryo, which is implanted into a surrogate mother, just as in standard embryo transfer, who carries the pregnancy to term.
How does cloning affect the DNA of animals?
Cloning does not change DNA and clones are not genetically modified organisms (GMO's). Clones are genetically identical to the original cell donor. Cloning is simply a form of assisted reproduction.
Is it safe to use clones in the food supply?
The U.S. Food and Drug Administration analyzed more than 100 scientific studies on cloning, encompassing years of safety data and several generations and large families of livestock. The FDA concluded: "The current weight of evidence suggests that there are no biological reasons to indicate that consumption of edible products from the clones of cattle, pigs, sheep or goats poses a greater risk than consumption of those products from their non-clone counterparts."
The National academy of Sciences (NAS) also scrutinized numerous studies, publishing in-depth reviews in 2002 and 2004. The NAS concluded that "there is no scientific evidence that cloning is associated with any unintended compositional change that results in an unintended health consequence in humans" and pointed out that consumers would get better food because clones have "increased genetic merit for increased food production, disease resistance and reproductive efficiency."
Are cloned animals healthy?
A National Academy of Sciences review found that "the health and well being of somatic cell clones approximated those of normal individual as they advance into the juvenile stage. Somatic cell cloned cattle reportedly were physiologically, immunologically, and behaviorally normal."
How does the neonatal mortality rate of cloned animals compare to other animals?
Any animal conceived through an assisted reproductive technique has a higher risk of neonatal death. In the hands of skilled scientists, the neonatal death rate of cloned animals approaches that of animals produced by in vitro fertilization. Within hours or days of birth, there are no health differences between clones and non-clones, according to an NAS review panel.
Is there a risk of Large Offspring Syndrome (LOS) among cloned animals?
LOS occurs naturally in cattle. It is seen at higher rates with assisted reproductive technologies and is not a problem caused specifically by cloning.
Will the clone of my top performing sire or dam perform just like the original?
Clones are genetically identical to the original cell donor, essentially identical twins separated in time. They have exactly the same genetic potential as the cell donor. However, they are brought up in a different environment at a different time. So, in as much as environment (e.g. nutrition, socialization, exposure to pathogens, etc.) can affect the ability to perform, behavior and appearance, clones may be different from each other and from the original cell donor.
Physical Appearance/Color Pattern
While clones usually have very similar hair color and appearance, some differences may exist. During fetal development the cells that produce pigment, melanocytes, migrate around the fetus. The final location of the cells is not completely controlled by genetics and can be affected by the uterine environment during development. So, the color pattern of a clone may be slightly different than that of the cell donor. For example, the clone of a spotted animal should also be spotted, but the spots may not be in the exact same location.
Because clones are genetically identical to the cell donor, the genetics that they pass on to offspring are identical to that of the cell donor. Breeding an animal to a clone will be equivalent to breeding to the original cell donor.