China scientists have used embryonic stem cells to create, by genetic editing, laboratory mice with two male parents. The animals thus created have managed to live until adulthood, although with significant developmental abnormalities. The realization is notable in the genetic engineering of mammals.
Scientists used mouse embryonic stem cells. Photo shutterstock
Chinese scientists have directed a certain set of genes used in reproduction to create a bipaternic downward descent.
Created mice come from two male biological parents, instead of a female and a male, which is called unisexual reproduction.
It is known that mammals multiply exclusively by sexual reproduction, while other vertebrates, including some reptiles, amphibians, birds and fish, have produced descendants by unisexual reproduction, by a phenomenon called partnogenesis in which an embryo is formed from an egg. without fertilization.
In the new study, published in Cell Stem Cell magazine, mice were created by genetic editing of mouse embryonic stem cells aimed at a class of mammalian genes, known as printed genes (about 200, according to researchers).
Stem cells are cells that can develop in various body tissues. Embryonic stem cells, present in incipient embryos, have the ability to transform into all types of fetus cells.
Most types of stem cells are less versatile and can help support and restore only the tissues and organs in which they are located.
In the mentioned study, scientists have modified 20 of the imprinting genes and used cloning technology to create bipaterni mice.
“In general, it was considered that printed genes serve as «.lock. » which prevent mammals from undergoing unisexual reproduction. However, this widely accepted hypothesis has not been conclusive so far ”said the biologist Wei Li from the Chinese Academy of Sciences, one of those who led the study.
The researcher said that “It is a fundamental scientific study focused on animal models. There are no plans to expand this type of experiments in people. ”
Scientists created 1,081 embryos, but of them, only about 12% survived until birth, much less than normal.
Development disorders have been found, including cranio-facial deformations
In total, 84 male chicks and 50 female chickens were born. More than half died before reaching adulthood. Those who reached adults had all developmental defects, had a short lifespan and were sterile.
“Bipaterial mice have presented developmental disorders, including cranio-facial deformations, in which the ratio between the width and length of their face was higher compared to normal mice. They also had difficulty in breastfeeding”, Declared the biologist Guan-Zheng Luo from Sun Yat-Sen University, the study co-author.
What behavioral anomalies have been found
The researchers designed a significant way of mitigating these two defects by inactivating a specific development gene.
“However, mice had still behavioral abnormalities, such as the tendency to enter the center of an open field, which is contrary to the instinctive behavior of rodents, which usually prefer to remain near the edges. The sterility of bipaterni mice may be due to excessive changes in printed genes, because these regions play various development roles ”, added Luo.
The aforementioned study is the latest research involving Bipaterni laboratory mice, according to Reuters.
If the research is perfected, it may prove valuable, according to scientists, in the efforts to prevent the extinction of endangered species and could be helpful in the field of regenerative medicine, which involves replacing tissues or organs damaged by diseases. or other factors.
