For mammals, it takes the DNA from a male and a female to create new life. Some animals can produce offspring from an unfertilized egg, called parthenogenesis. Scientists have been trying for years to create life from the DNA of same-sex parents in mammals, and now, they’ve finally succeeded.

The basics for life

Mammalian biology requires two sets of chromosomes from the gametes of two parents to produce progeny. Each gamete, an egg cell and a sperm cell, carries half of the required genetic material to create a new being. While attempts have been made to combine the genes from two sperm cells or two egg cells, none had been successful until recently.

Wise Geek

In 2004, Japanese scientists saw the birth of baby mice created from the DNA contained within two egg cells. Those mice were the first of their kind to survive into adulthood.

New discoveries

The primary setback for scientists before the 2004 experiment was that they were using unaltered genetic material in their attempts to create new offspring from same-sex parents. The DNA in the successful test had been altered through a process called imprinting.


The DNA contained within different-sex gametes fit together like puzzle pieces, each one being coded slightly differently than the other. Paternal DNA has different genes turned on or off than maternal DNA, and the differences are essential to producing viable young.

Flipping switches

To make young that would survive outside of the womb from same-sex parents, scientists needed to go in and manually alter the genetic code from one of the parents so that, to the other set of DNA, it looked like it came from the other sex. Modifying the genetic code of egg cells has proven much more manageable than doing the same with sperm cells.

Human Rights Campaign

If the process of altering genes can be perfected, it could revolutionize the reproductive world. Possibilities for selective livestock breeding and cloning might not be far off. Once the technology advances far enough, same-sex couples might even be able to have biological children of their own.