The Food and Drug Administration announced in January that meat and milk from cloned animals was as safe to eat as that from traditional animals. However, the Agriculture Department asked the cloning industry to prolong the ban on marketing such foods during an expected “transition” period of several months. Steven Sundlof of the FDA said it might be several years before widespread commercialization, since cloned animals need to mature and provide sufficient offspring.

This raises the same concerns voiced during the past two decades against genetically modified (GM) food crops. In both cases, for-profit industries are creating new life forms with unpredictable consequences. As opposed to the industry claims, it is not the same as the centuries-old methods of cross-breeding within the same species to select offspring with superior qualities, e.g., sweeter corn.

The more recent cloning uses somatic cell nuclear transfer — for example, the nucleus from a skin cell of a prize cow is introduced into a cow egg from which the original nucleus has been removed, and this egg is then implanted in the uterus of a “surrogate” mother cow to bring the embryo to term. This “reproductive” cloning (first used to produce Dolly the sheep) is very inefficient and expensive. More than 90 percent of cloning attempts fail, with over 40 percent of “successful” clones suffering from obvious debilitating health problems leading to premature death. The National Academy of Sciences concluded that hidden defects in cloned animals could pose food safety risks.

Why would cloned animals have imperfections? The specific reasons are not known, but using the genome from a differentiated cell, such as a skin cell, of a mature animal to create a new embryo is using an “aged” genome that has been programmed for very specific functions. The specific genes for that program must be silenced and genes necessary for the development of a new complete individual must be turned on. This reprogramming is suspected to account for observed deformities in cloned animals, such as enlarged tongues, squashed faces, intestinal blockages, immune deficiencies, tumors and diabetes. In addition, cloned animals are given large doses of antibiotics to ward off higher rates of infections.

The surrogate mothers suffer from many pregnancy complications, for example, bearing grossly oversized offspring, and are often given massive doses of hormones which are added, along with antibiotics to the clones, into the food supply.

Michael Appleby of the London-based World Society for the Protection of Animals said: “These are animals. They’re not just economic units … They’re not just machines.” Cloned animals will add another practice to the inhumane and cruel treatment of “factory-farmed” animals.

Life has evolved during billions of years. There is a sensitive balance between species and their variants, from the bacteria that inhabit our intestines to higher primates. Rapid introduction of new manmade kinds of life will very likely have a negative impact on this long-term selection. Imagine throwing a rock into an engine: there is a very small but finite possibility that it will improve engine performance, but smart money will bet performance will be decreased by interfering with the balance of all the parts selected after years of research.

This scientific perspective has an analogous counterpart in the religious objections that regard introduction of new life forms by people to be usurping the province of God.

As with GM crops, the justification for cloned animals is to produce food products that are better for human consumption and to help feed the world’s population. However, as reported by a United Nations commission, the main problem of hunger and famine in the world has not been a result of food shortages, but rather of food distribution.

Furthermore, the real goal of factory farming of crops and animals is to lower costs and flood the markets with low-priced foods. This drives native farmers out of business. It has happened to corn farmers in Mexico and farmers in other Latin American countries, and accounts in large part for the massive influx of unemployed Latinos into the U.S. As long as the primary goal of food production is to generate profits, feeding people will remain a distant secondary, or nonexistent, goal.

Sen. Barbara Mikulski (D-Md.) and Rep. Rosa DeLauro (D-Conn.) have introduced legislation to require labeling products from cloned animals and their offspring. At least, consumers would have a choice, but this would be best served if products from cloned animals were banned completely from the food supply.

David Kennell ( is professor emeritus of molecular microbiology at Washington University School of Medicine in St. Louis.