The first cloned cat was named CC, short for “CopyCat” or “Carbon Copy.” CC was born on December 22, 2001, at Texas A&M University. Her birth marked the first successful cloning of a domestic cat and the first cloned pet in the world. This demonstrated the feasibility of cloning companion animals, paving the way for the commercial pet cloning industry.
The Scientific Method Used
The technology used to create CC was Somatic Cell Nuclear Transfer (SCNT), the same technique used years earlier to clone Dolly the sheep. SCNT is a laboratory procedure that creates a viable embryo by combining a body cell and an egg cell. This process requires three primary steps to reprogram an adult cell to act like a newly fertilized egg.
The first step involves obtaining a somatic cell, which is any non-reproductive cell from the donor animal, and collecting its nucleus containing the complete genetic information. Simultaneously, an unfertilized egg cell (oocyte) is taken from a female donor, and its nucleus is removed (enucleation). This leaves an “empty” egg cell that provides the necessary cellular machinery but lacks the original DNA.
In the second step, the nucleus from the donor’s somatic cell is inserted into the enucleated egg cell. The reconstructed egg now holds the complete genetic material of only the donor cat. This procedure tricks the egg into accepting the new nucleus and behaving as if it had been fertilized naturally.
Finally, a mild electric shock or chemical stimulation is applied to activate the reconstructed egg and trigger cell division. If successful, the cell develops into an early-stage embryo called a blastocyst, which is then implanted into a surrogate mother for gestation. Although genetically identical to the donor animal, the cloned embryo’s development can still be influenced by the egg cell’s environment.
The Historical Context of the Project
The cloning of CC resulted from a $3.7 million research initiative at Texas A&M University. The project initially focused on cloning a mixed-breed dog named Missy, belonging to John Sperling, the founder of the University of Phoenix. This effort, dubbed the “Missyplicity Project,” was funded by Sperling, who had a commercial interest in pet cloning.
Researchers found that dogs proved difficult to clone successfully. Due to the technical challenges with canine cloning, the research focus shifted to felines, which were more manageable subjects for SCNT. This pivot led to the specific effort informally known as “Project CopyCat.”
The purpose of the cat cloning was to demonstrate the technology’s feasibility in companion animals, laying the groundwork for a commercial service. Sperling had established Genetic Savings & Clone Inc., which controlled the commercial rights to the Texas A&M cloning process. CC’s birth in late 2001 served as a proof of concept for the company’s future business model.
The Cat’s Appearance and Scientific Legacy
CC was cloned from a female calico cat named Rainbow, which had white, black, and orange patches. Despite sharing the exact same nuclear DNA, CC’s coat was white with a gray tabby pattern and lacked the distinctive orange patches. This unexpected difference showed that a clone is not an exact, physical duplicate of its donor.
The discrepancy in coat color is explained by X-chromosome inactivation, or Lyonization, a process that occurs in female mammals. Female cats have two X chromosomes. To balance gene expression, one X chromosome is randomly “shut off” in each cell early in embryonic development. Since the genes for orange and black fur color are located on the X chromosome, this random inactivation determines which color is expressed in a given patch, creating the mosaic calico pattern.
The cell used to clone CC was taken from Rainbow’s ovary, but that specific cell had already undergone X-inactivation, permanently silencing the X chromosome carrying the orange color gene. Therefore, CC had the genetic instructions for a calico coat, but the cellular starting material dictated that only the gray and white colors could be expressed, resulting in her distinct appearance. This outcome highlighted the role of epigenetics—changes in gene expression without altering the underlying DNA sequence—in shaping an organism’s final traits. CC lived a long, healthy life and gave birth to a litter of kittens.