Half & half
By Erin DeJesus, Metrosource, October-November 2005

She has her father’s eyes….and her other father’s smile.

In a world where gay marriage and stem cell research are already divisive issues, the thought of biologically engineering children from either two sperm or two eggs might seem like a form of leftist science fiction. But in July, scientists in the UK proved that eggs and sperm could be grown from embryonic stem cells-making it possible for a man to produce an egg and a woman to produce a sperm. For gay couples, this will be the first time there has been (theoretically) a chance for both parents to be biologically linked with their child.

Stem cells are early biological forms that will-eventually-turn into specialized cells of the human body (like skin cells, blood cells, etc.). Because all cells in the body have the same DNA, stem cell technology has focused on re-programming these stem cells to take on specific forms.

“There are modifications of the DNA that [naturally] allow cells to know what kind of programming it has,” said Dr. Richard T. Scott, director of the Foundation for Advanced Reproductive Science. “If you simply knew how to arrange those sugars and proteins in the way they attach to the DNA, you could differentiate a cell in a way that could allow it to behave like an egg or a sperm.”

The newly discovered process, called dedifferentiation, can modify stem cells from either sex into their gamete forms, both sperm and egg. Like “regular” sex cells, the engineered versions each have their own distinct set of chromosomes and genetic material.

“This is not a way to control which way the genes or chromosomes go,” Scott said. “The natural mechanisms that determine that will be just the same. This is getting the cells back to the point where nature can take its course.”

From there, in order to achieve pregnancy, the couple’s two distinct sex cells, sperm and egg, will join through the standard in-vitro fertilization process. While gay men will still need a gestational carrier to carry the child to term, her genes will be nowhere to be found.

While the process is still a long way off, its implications raise eyebrows, as gay baby-making already has its share of complexities.

Currently, couples can choose only one partner to serve as the genetic link to their child, via sperm or egg donation, or a gestational carrier. According to attorney Melissa Brisman, who specializes in reproductive law, couples must then tackle a variety of contracts, court orders and personal decisions regarding custody issues and parental rights.   

Considering this legal rigamarole and – in some places – heavy political and religious opposition to gay parenting, more “traditional” forms of gay conception are complicated enough. If and when the technology to create a new biological child becomes legitimate, the legal and political aspects – which already vary greatly from state to state- will be forced to catch up quickly.

“In my mind, it’s definitely science fiction right now,” Brisman said. “But all these new technologies will make the law a lot harder to follow.”  

If not entirely science fiction, the possibility is still futuristic at best. The speed of the technology’s development relies heavily on funding and testing, and even if funding is strong, it will still be a few years until scientists can achieve dedifferentiation in human cells. After that, extensive testing is necessary to make sure the procedure is safe for the child, and scientists will probably have to follow a test subject well past the embryonic stage.

The subject will most likely need to be watched well through puberty and its own reproductive cycle in order to ensure it is undergoing normal development – but, naturally, that means a second generation of babies.

“It’s not completely figured out yet; it’s not something people will be implementing tomorrow in their clinics,” said Scott. “There’s no proof you can make human germ cells yet. It’s certainly being worked on, but it’s not done.”

But even as scientists continue to caution that the possibility sits far in the future, it seems likely that among couples – gay or heterosexual – who cannot conceive “naturally,” the demand will be great. “Most people would like that genetic connection if they can have it,” said Dr. Andrea Braverman, director of psychology at Reproductive Medicine Associates of New Jersey. “Most of us just grow up assuming that we’re going to have that connection.”