The "Three's Company" episode where they discuss bioethics

Last February the UK Telegraph announced that British scientists had created an embryo with three parents. Researchers at the University of Newcastle took the nucleus of an embryo produced during assisted reproduction and placed it inside an egg from which the original DNA was removed, leaving behind the donor's mitochondria. Thus, the resulting embryo contained genetic contributions from three people.
The researcher's goal is to create a procedure to prevent mitochondria-related diseases.
Although, these diseases are rare, the results can be devastating. By using the Newcastle method, a traditionally-formed embryo with a defective mitochondria could then be replaced with functional mitochondria.

The Telegraph explained that “in effect, the new technique would be like changing a battery in a computer without affecting the hard disk, the nuclear DNA that influences our appearance and other characteristics, so that an affected woman does not pass them on to her children.”

http://www.telegraph.co.uk/scienceandtechnology/science/sciencenews/3324321/Transplant-creates-embryos-with-three-parents.html

At this time, the legality of the operation in England is still in question.

Although the Telegraph piece focused on the pathological implications. The internet instantly buzzed about the cultural possibilities. A Wired.com article explained that the Newcastle procedure might be useful for people in a trinogamous relationship or “a long-term union of three people rather than two.” (The article notes that linguistically binogamous would be proper, however, the class of individual for which the term applies have apparently already taken the aforementioned term).
The article explains that “like anyone else, people in trinogamous relationships may want to have children with DNA from all the parents. Enter the Newcastle method. The same holds for same-sex couples for whom an embryo conceived through traditional assisted reproduction contains DNA from only one partner.”
http://blog.wired.com/wiredscience/2008/02/calling-jerry-s.html

Although I tend to believe that a human family is best structured around a monogamistic center (be of it any combination of gender and sex), I am not opposed to a trinogamous child. Indeed for individuals opposed to monogamy, such a unique child would certainly be an incredible way to reinforce their non-monogamistic union. As I type this, I'm finding more and more that I have strong conservative feelings as to monogamy; still, as I do not know any trinogamous individuals I can't get myself to judge such domestic situations as wrong per se.
On the other hand, in the event such a trinogamistic societies are structured around one male and multiple females I might be concerned with the implications of encouraging such domestic situations. Although, HBO's Big Love does make a relatively strong case for polygamy.
(incidentally the DNA used in the Newcastle method happened to be 2 women and 1 male).