Researchers produce mouse pups with same-sex parents.
It is known that some reptiles, amphibians, and fish can reproduce with same-sex parents, however, it’s challenging for mammals to do the same even with the help of fertilization technology. Now, a study from researchers at the Chinese Academy of Sciences produces healthy mice with two mothers that went on to have normal offspring of their own. The team state their study explores what makes it so challenging for animals of the same sex to produce offspring and suggests that some of these barriers can be overcome using stem cells and targeted gene editing. The opensource study is published in the journal Cell Stem Cell.
Previous studies show that certain maternal or paternal genes in mammals are shut off during germ line development by a mechanism called genomic imprinting, meaning that offspring which don’t receive genetic material from both a mother and a father might experience developmental abnormalities or be unviable. By deleting imprinted genes from immature eggs, researchers have produced mice with two mothers. However, the generated mice showed defective features. The current study investigates whether normal mice with two female parents, or even mice with two male parents, could be produced using haploid embryonic stem cells with gene deletions.
The current study utilises haploid embryonic stem cells which contain half the normal number of chromosomes and DNA from only one parent, and created the mice with two mothers by deleting three imprinting regions of the genome from the haploid embryonic stem cells containing a female parent’s DNA and injected them into eggs from another female mouse. Results show that twenty-nine live mice were produced from 210 embryos. Data findings show that the mice were normal, lived to adulthood, and had offspring of their own.
The lab state they also produced twelve live, full-term mice with two genetic fathers with a similar procedure, however these pups only survived 48 hours after birth. They go on to add that their data reveals some of the most important imprinted regions that hinder the development of mice with same-sex parents, which are also interesting for studying genomic imprinting and animal cloning.
The team surmise their study shows that the defects in bimaternal mice can be eliminated and that bipaternal reproduction barriers in mammals can also be crossed through imprinting modification. For the future the researchers state they plan to explore these techniques in other research animals.
Source: Chinese Academy of Sciences