It’s four o’clock in the morning, the milking machines at a dairy farm in Somewhere, USA are being attached to the utters of 700 cows to begin the day’s liquid harvest.. Most of the 700 cows are the offspring of natural birth, but many are the result of unnatural births by means of cloning. The milk travels down stainless steel pipes eventually empting into large refrigerated bulk tanks mixing both the cloned and uncloned milk.
This scenario is very possible according to Dr. Allison L. Von Eenennaan; Animal Genomics and Biotechnology Extension Specialist, (Department of Animal Science, UC Davis). Von Eenennaan states that it would be extremely difficult to safely keep the five gallons that come from Bessie the clone separated from the 55 gallons that come from Elise and the girls who where born naturally. And, it would be very expensive to implement a separation process.
Just what is cloning, and how does it work?
When scientists explain the practice of cloning livestock, they describe clones as genetic twins born at different times. Cloning companies say it’s just another reproductive technology, such as artificial insemination.
“The lead cow (the one in front) gets whipped the most.” – African Proverb, Zulu.
Here is how cloning works: Scientists take an immature egg, usually from a cow that went to the slaughterhouse, and remove the nucleus. They add DNA from a designated cow, often taken from the skin cell of an ear, and a tiny electric shock coaxes the egg to start dividing and grow into a copy of the original animal. The egg is then implanted into a surrogate animal for gestation and birth, and the egg subsequently grows into a fetus.
The term “clone” is derived from the Greek word for “twig, branch,” referring to the process whereby a new plant can be created from a twig. In horticulture, the spelling c-l-o-n was used until the twentieth century; the final “e” came into use to indicate the vowel sound is a “long o” instead of a “short o.” Since the term entered the popular lexicon in a more general context, the spelling c-l-o-n-e has been used exclusively.
Hundreds of cloned animals exist today but the number of different species is limited. Attempts at cloning certain species such as monkeys, chickens, horses and dogs, have not been documented.
These early stages of reproductive cloning have been expensive and highly inefficient. More than 90 percent of cloning attempts have reportedly failed 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. Japanese studies have shown that cloned mice live in poor health and die early. About a third of the cloned calves born alive have died young and many of them were abnormally large. Many cloned animals have not lived long enough to generate acceptable data that could inform scientists about how clones age. Appearing healthy at a young age, unfortunately, is not a good indicator of long term survival. Clones have been known to die mysteriously.
The FDA and package labeling
The Food and Drug Administration (FDA) issued to U.S. food producers an approval to begin selling meat and dairy from cloned animals and their offspring. Some consumer groups question the long term safety of consuming meat and milk from clones. But the FDA reports that their assessment has been peer-reviewed by a number of independent, (but pro) cloning and health experts, who agree that livestock cloning is not only safe but “poses no unique risk to animal health when compared to other assertive reproductive technologies currently in use in U.S. agriculture.” In December of 2006, the FDA released a draft of its animal clone safety assessment, concluding that “meat and milk from clones of adult cattle, pigs, goats and their offspring are (as) safe to eat as food from conventionally bred animals.”
Today, there are approximately 600 cloned animals living in the United States. Most were produced for show, (at state fairs and a few for the Rodeo industry). ViaGen, has produced about 300 of these 600 cloned animals, primarily cattle.
Food derived from animal clones will likely not hit the market for at least four or five years. And even then consumers will likely not eat a pork chop made from a cloned pig or drink milk from a cloned cow. Rather, they primarily would be consuming food made from naturally born animals that are the progeny of clones.
U.S. consumers feel strongly about clone labels and support label enforcement when cloned meat is made available at local supermarkets. As part of its ruling, the FDA decided not to require labels. But several states, (including California) have taken the issue of labeling to their state capitols. Bills have been introduced in state legislatures across the country that call for words or symbols alerting shoppers to the presence of cloned foods
Across the country the language in all the bills is similar and strong. For instance, the Kentucky bill that was just recently introduced and is waiting a vote by its state legislature reads in part, “No person shall sell, offer or expose for sale, have in his possession for sale, or give away, for human consumption, any fresh or frozen meat, meat preparation, meat by-products, dairy food or dairy food product or poultry or poultry product derived from a cloned animal or its offspring unless the product is clearly and conspicuously labeled as such.”
There are those who work in the field who feel that labeling will kill the business before it starts. Some food experts agree. “The problem with labeling is that it implies that something is wrong with the food,” said William Hallman, director of the Food Policy Institute.
In all actuality if past battles over genetically modified foods are any indication, clone-labeling requirements may never see the light of day. In 1992, genetically modified food was given the green light by the federal government. (That’s right, we’ve been eating cloned or as it is called, genetically modified vegetables, e.g., corn, peas, peanuts and soybeans, for over 15 years). Within days of the ruling, at least 16 states introduced bills that called for labeling of such food. None became law.
In a recent Pew Research poll, more than 64 percent of Americans say they are uncomfortable with animal cloning and 43 percent say they believe food from cloned animals is unsafe. Executives at companies involved in the animal cloning business admit they are battling great opposition. Mark Walton, president and CEO of ViaGen an Austin, Texas-based gene bank and cloning service said, “Much of what people have heard about cloning is from sci-fi and horror movies. And, the hero is never a clone.”
Cloning and Xenotransplantation
Some day, the therapeutic technology of cloning may very well be used in humans to produce whole organs from single cells or quite possibly to produce healthy cells that can replace damaged cells in degenerative diseases such as the life depleting illness Alzheimer’s or Parkinson’s. It is without question that there is much work to be done before therapeutic cloning can become a realistic option for the treatment of human disorders, and most likely this may be years to come.
Scientists report one very interesting potential application of cloning and organ transplants. It is the creation of genetically modified pigs from which organs suitable for human transplants could be harvested. Often, the organs of pigs are studied and used in medical and biological studies. This process, the transplantation of organs and tissues from animals to humans, is called xenotransplantation.
Why pigs? Would not primates be a closer match genetically to humans? A good question indeed; and the answer is yes, but they are more difficult to clone and have a much lower rate of reproduction (a very real downside). Of the animal species that have been cloned successfully, pig tissues and organs are more similar to those of humans. Today those in the coloning field are trying to create a “knock-out” pig. Scientists must inactivate the genes that cause the human immune system to reject an implanted pig organ. The genes are knocked out in individual cells, which are then used to create clones from which organs can be harvested. The gene which can potentially cause organs to be rejected produce an enzyme that adds sugar to the surface of pig cells. This enzyme was isolated in 2001 by the PPL Therapeutics, U.S. Division, a biotechnology company for the purposes of inactivating it. The reason the isolation and inactivation of the gene was critical to the xenotransplantation process is that scientists could now block organ rejections.
Cloning embryonic stem cells and the ‘cure’ of sickle cell
One of the most promising and most controversial area of cloning is that of embryonic stem cell research. Scientist, physicians, and other genetic experts rave about its potential to advance medicine to unlimited proportions. They say the use of stem cells could lead to successfully treating and quite possibly curing diseases such as, Parkinson’s, blindness, spinal cord injuries, cancers and blood disorders like sickle cell.
In addition, because of their plasticity and potentially unlimited capacity for self-renewal, embyonic stem cells can become any tissue in the body. As one can imagine, any damaged cell can be replaced with a brand new one.
Sickle cell anemia is a serious condition that affects millions of people worldwide and most commonly seen in people of color. It is found in individuals whose families come from Africa, South or Central America (especially Panama), the Caribbean, Mediterranean countries (such as Turkey, Greece and Italy), India and Saudi Arabia.
Sickle cell is a condition in which the red blood cells in ones body can become sickle-shaped instead of smooth and round. Because of this, the cells can’t move as easily through the blood because they are stiff and sticky, often forming clumps and clots in the blood vessels. This of course can be and often is very, very painful. It also can and does result in death (about 83% of the time).
Today, sickle cell anemia affects nearly 70,000 people in the United States, primarliy African Americans. And, almost 2 million Americans have the sickle cell trait.
Currently, the only cure for sickle cell is bone marrow transplantation. This treatment is performed on patients with severe sickle cell. However, it is very rare, partly due to the fact that the donation of bone marrow is very low in the African American community.
Because of embryonic stem cell research, scientists in the U.S. have made a breakthrough in the fight against sickle cell anemia. This research could be more advanced however if scientists were allowed to clone embryos to harvest more embryonic stem cells. (This is currently against U.S. policy.) Centered around the research involving the creation, usage and destruction of human embryonic stem cells, this is also an ever increasing ethical issue. So as sickle cell patients wait out this controversy, for now the only cure remains bone marrow transplantation.
Some cutting edge scientists have attempted to overcome the limits on stem cell research by working with adult skin cells rather than embryonic stem cells.. These are ips cells and the process is to genetically modify adult skin cells by purposefully introducing a virus. However, once the ips cells are implanted into bone marrow of mice impacted with sickle cell, a by product of the virus is cancer….therefore, curing the sickle cell anemia, but introducing cancer would be the undesirable trade off currently.
There is one thing for sure, cloned food has already found its way in our produce section. A minute amount of cloning has entered our healthcare system and cloning is likely to be on the horizon of the next frontier of our lives.
