It doesn't seem that long ago when an outcry was raised over Dolly the Sheep, the first animal to be created through cell cloning. Now, if a Chinese researcher is to be believed, we have made the leap to cloning animals to genetically editing our own offspring.
The researcher, He Jiankui of Shenzhen, says the twins known as Lulu and Nana "came crying into the world as healthy as any other babies" several weeks ago, and are now at home with their parents.
He, together with a Chinese team and the assistance of a US scientist -- who traveled overseas as such DNA alteration is currently banned in the United States -- were able to overwrite and tamper with the twins' DNA through the gene modification tool CRISPR, according to the Associated Press.
The purpose? Medical alteration and resistance to disease, namely, the HIV/AIDS virus.
Embryos provided by seven couples were altered, with one successful pregnancy so far. According to the scientist, the successful pregnancy, resulting in twins, was achieved using the sperm of a man known as Mark who is an HIV carrier and "never thought he could have children."
See also: Before taking that DNA test: Six things you need to know
"Grace [the mother] started her pregnancy with one difference; after we sent her husband's sperm into her eggs, we also sent a little bit of protein and some instructions for a gene surgery," He says. "When Lulu and Nana were just a single cell, this removed the doorway through which HIV enters to infect people."
The protein doorway is used by a gene called CCR5 which permits HIV to enter cells. It is this gene that the team focused on editing.
He added that a few days later, the team performed gene sequencing to see if the changes had taken root. According to the scientist, the "surgery worked safely, as intended," and no other gene was modified.
CNET: New gene-editing 'pencils' rewrite DNA to erase disease
However, the trial was conducted in secret and no paper has yet been presented for the scrutiny of peers in the genetic sequencing and editing space.
The identities of the parents and children involved in the trial -- which some have blasted as reckless human experimentation and dangerous -- have also been kept anonymous.
If such claims turn out to be true, this is a major milestone in science which could result in a generation born with inherent resistances to some of the most debilitating diseases in existence. Such a future does, however, also raise a number of ethical questions and the possibility of a slippery slope when it comes to 'designer' children and what DNA could -- or should -- be altered.
The research, which has not been independently verified, was revealed ahead of a conference on gene editing due to start in Hong Kong on Tuesday.
TechRepublic: DIY genetic engineering is about to explode
The tool apparently used to conduct the experiment is known as Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR/CRISPR-Cas9), a genome-editing tool based on a naturally occurring editing system in bacteria. By using CRISPR, dangerous genes can be disabled.
Scientists worldwide are still exploring the potential applications of the tool, but for some, tampering with the DNA of humans may have come too soon.
"This is far too premature," Dr. Eric Topol from the Scripps Research Translational Institute in California told the AP. "We're dealing with the operating instructions of a human being. It's a big deal."