Mouse pups have been born from same-sex parents by Qi Zhou and Wei Li, researchers at the Chinese Academy of Science (CAS).
The First Successful Experiment Through Genomic Editing and Stem Cell Technology
This is the first case of parthenogenesis in mammals, which means reproduction from same-sex parents. Even though many scientists had tried for a long time to succeed in mammal parthenogenesis, it could not be accomplished because of the phenomenon called genomic imprinting. Genomic imprinting refers to the phenomenon that makes genes from only one of the parents expressed. It occurs to prevent possible genomic abnormalities when genes from both parents are expressed.
To solve this problem, the research team used genomic editing and stem cell technology. First, they created haploid embryonic stem cells from female mice through genomic editing. Haploid cells contain half of all chromosomes, so they only have half of deoxyribonucleic acid (DNA). Then they removed genetic regions, parts of the genes controlled by genomic imprinting, from the cells. After the removal, the cells without genetic regions were injected into the ova of surrogate mice. As a result of the experiment, 29 healthy mouse pups were born from 210 embryos, seven of which even produced their own offspring. They were all female because their genes were inherited from two mothers.
Remaining Challenges and Significance
In a similar way, the research team also succeeded in male parthenogenesis. Unlike those with two moms, the mouse pups from two dads, however, all died within two days, so the team has been working on revealing the causes for it. Furthermore, they said that they would apply this experiment to other mammals such as monkeys. Through the study, Qi Zhou and Wei Li have opened the possibility of finding out why mammals need gametogenesis, reproduction from parents with different sexes. Also, it can be a clue to curing diseases attributed to errors in genomic imprinting. The related paper was published in the famous scientific journal Cell Stem Cell on October 12th.