Overcoming Barriers to Unisexual Reproduction
Scientists have been attempting to induce single-parent reproduction in mammals for decades. While bi-maternal mice were first created over 20 years ago, achieving the same with two male parents was more challenging. The breakthrough was made possible through embryonic stem cell engineering and manipulation of imprinted genes. These genes are typically inherited from one parent and silenced from the other, making their correction crucial for successful development.
The researchers reported in the journal Cell Stem Cell that they corrected 20 imprinted loci, allowing the successful development of bi-paternal mice. “These findings provide strong evidence that imprinting abnormalities are the main barrier to mammalian unisexual reproduction,” said Luo Guanzheng, co-corresponding author of the study. The research could also have implications for regenerative medicine and cloning techniques.
Challenges and Limitations
Unlike certain lizards that can reproduce asexually, mammals have never naturally produced offspring without genetic material from both male and female parents. One of the key challenges in artificial unisexual reproduction has been imprinting genes, which regulate developmental processes. Disruptions in these genes can cause embryos to fail in development.
Qi Zhou, a corresponding author from CAS, explained, “The unique characteristics of imprinting genes have led scientists to believe that they are a fundamental barrier to unisexual reproduction in mammals.” The new study confirms that modifying these genes can help overcome this obstacle, but challenges remain.
The success rate of the technique is low, with only 11.8% of viable embryos developing to birth. Many of the born mice did not survive to adulthood, and those that did showed abnormal growth patterns and shorter lifespans.
Future Research and Implications
The researchers plan to refine their technique to improve viability and address health issues in bi-paternal offspring. Their next phase of study will focus on larger animal models, such as monkeys, to test the feasibility and safety of the approach in more complex organisms.This breakthrough could have long-term implications for reproductive technology and genetic engineering, but ethical and biological challenges remain. Further research will determine whether this method can be applied beyond laboratory conditions.