For the first time in history, a group of babies was born with three sets of DNA each.
It happened in the U.K., which in 2015 became the first country to allow scientists to genetically modify eggs of women with damaged mitochondria (the cell's energy hub) to avoid the passage of mitochondrial defects on to children. Such defects are incurable and often fatal - intervention is the only way these women can have healthy kids.
Here's what happened...
Scientists transferred genetic material from eggs with damaged mitochondria to donor eggs that had healthy mitochondria but all other DNA removed. The eggs were then fertilized and transferred into the wombs of the mothers.
It's important to note that the genetic material from the donated egg comprises less than 1% of the child created from this technique. But that 1% makes a massive difference...
Many in the scientific community celebrated this landmark event as a new way for women to have healthy kids who otherwise can't. Others are deeply concerned.
“It will be interesting to know whether there's risk of these kids developing problems later in life,” Robin Lovell-Badge, a well-known British stem cell expert said.
Then there's the prospect of so-called "designer babies" - now that it's been established mitochondria can be controlled for, it's clear that non-life-saving variables like height and natural strength can be manipulated.
It's not my place to comment, but one thing is clear to me: genetic intervention isn't slowing down. This is a phenomenon everyone should stay aprised of.