It is clear from studies FDA reviewed on animal health that clones hav — Cloning

"Why do we need therapeutic cloning? As a layman, several important reasons come to mind. One, implantation of human embryonic stem cells is not safe unless they contain the patients own DNA. Two, efforts, to repair central nervous system disorders may need to recapitulate the process of fetal development, and that could only be accomplished by human embryonic stem cells. Three, therapeutic cloning is done without fertilizing an egg. It can be strictly regulated. If we also enforce an absolute ban on reproductive cloning, we will not slide down the dreaded slippery slope into moral and ethical chaos. Any powerful new technology comes with the possibility for abuse. But when we decide that the benefit to society is worth the risk, we take every possible precaution and go forward. The unfertilized eggs that will be used for nucleus transplantation will never leave the laboratory and will never be implanted in a womb. But if we do not make this research legal, if we do not use Government funding and oversight, it will happen privately, dangerous unregulated and uncontrolled."

"In sum, there is a unique risk posed by SCNT clones that is not posed by other ARTs (artificial reproductive technologies): the potential for aberrant nuclearmitochondrial interactions. Embryos created via SCNT embryos differ from those created by other ARTs in two ways: they may be heteroplasmic (e.g. contain mtDNA from two sources) and nuclear-encoded mitochondrial DNA transcription and translation factors persist in SCNT, but not IVF, embryos."

"Given the paucity of data that directly address the safety of meat and milk from cloned animals, the FDA used indirect measures of food safety, primarily data on the health of the clones at different life stages. The operating hypothesis is the notion that an animal that appears healthy must be safe to eat (e.g. the Critical Biological Systems Approach). This approach is not scientific—this is reasoning by inference, not from data. Furthermore, FDA has bent over backward to interpret data from cloning companies in a way that minimizes the potential problems raised by SCNTs. Both of these problems need to be remedied in the final Risk Assessment."

"Reproductive cloning is expensive and highly inefficient. More than 90% of cloning attempts fail to produce viable offspring. More than 100 nuclear transfer procedures could be required to produce one viable clone. In addition to low success rates, cloned animals tend to have more compromised immune function and higher rates of infection, tumor growth, and other disorders."

"A number of researchers have noticed similarities between some of the mitochondrial depletion diseases in humans and some of the abnormalities seen in SCNT and hypothesize that aberrant nuclear-mitochondrial interactions in SCNTs could be responsible for some of these abnormalities. A research team in Germany found that “A survey of perinatal clinical data from human subjects with deficient mitochondrial respiratory chain activity has revealed a plethora of phenotypes that have striking similarities with abnormalities commonly encountered in SCNT fetuses and offspring. We discuss the limited experimental data on nuclear-mitochondrial interaction effects in SCNT and explore the potential effects in the context of new findings about the biology of mitochondria” (Hiendleder et al. 2005: 69). Researchers in the United Kingdom have suggested that potential overpopulation of mitochondria could lead to the large offspring syndrome often seen in SCNT cow clones and call for more work in this area: “a cytoplasm over-populated with mitochondria would lead to cellular expansion that might be indicative of the reported large-offspring syndromes. This under-researched area of investigation could provide clear answers to some of the developmental abnormalities witnessed in NT offspring and aborted feotuses, whether mediated through failure of somatic cell reprogramming or independently” (St John et al. 2004: 638-639)."

"FDA notes that "early reports, beginnning in 1998, of clone moraltiy rates were 50 to 80 percent," but states that more recent studies show better results, with mortality rates dropping to around 20%."