Eighteen years ago, scientists took DNA from a sheep and transferred it into the egg of another and then grew it in an embryo and transplanted into a third sheep - and the first mammal to be cloned from an adult stem cell, "Dolly" the sheep was born.
The same technique recently was used with skin cells from a 35-year-old and a 75-year-old man. DNA was taken and put into donor eggs of women. Those were then grown into embryos, according to a study published in Cell Stem Cell.
Some the cells were used to create embryonic stem cell lines that are personalized to the patient. The cells then could be programmed to create any cell that needs to be replaced due to disease, according to researchers.
Dr. David Agus, director of the USC's Westside Cancer Center in Los Angeles and a CBS News contributor said on "CBS This Morning" that the discovery is significant because as people age, they are more prone to diseases.
"There can be a stroke, problems with the heart, problems with the liver, etc. And now we can have the potential of creating personalized stem cells - taking your DNA and fusing them with an egg from a woman and then actually creating cells that can repair these diseases," Agus told "CBS This Morning."
The research is still in its early stages, but the discovery offers a glimmer of hope for radically changing the way doctors treat diseases -- by having the ability to create the specific cells needed to combat the illness, Agus said.
"There's a hundred kinds of immune systems so potentially you can create a hundred drugs of cell lines for individuals that change these diseases," he said.
While this latest advancement in stem cell research brings scientists and doctors a step closer to unlocking cures for a range of diseases, it's not without its problems.
In addition to not being scalable yet, Agus said it also poses some risks to women.
"Taking eggs from a donor woman has significant side effects potential for the woman, but this is just the beginning. But it really shows the potential for stem cells," he said.
Bioethics interest groups have also raised concerns over potential misuse of the technology.
"No one wants to wake up to headlines that a rogue fertility doctor or scientist initiated a pregnancy with a cloned human embryo," Marcy Darnovsky, executive director of the Center for Genetics and Society, a public interest organization based in Berkeley, Calif. said in a statement in response to the latest discovery.
Full use of this type of stem cell therapy is still decades away but when asked whether this latest development would eventually pave the road to cloning humans, Agus hoped it would not.
"But it's an issue we need to face," he said.
To see the full interview with Dr. David Agus, watch the video in the player above.