Lab-Grown Human Eggs Created from Skin Cells

• Scientists report early success in generating functional human eggs from skin cells, offering a potential future path for infertility treatment.

Researchers have taken a significant step toward creating human eggs from skin cells, according to a study published in Nature Communications. The experimental process involves transferring the nucleus of a woman’s skin cell into a donor egg that has had its own nucleus removed. This technique could one day help individuals with dysfunctional or absent eggs conceive genetically related children. While the findings are preliminary, they open new possibilities in reproductive medicine.

Overcoming Chromosomal Barriers with Mitomeiosis

One of the main challenges in converting skin cells into eggs lies in their chromosomal makeup. Human eggs contain 23 chromosomes, half the number found in typical body cells, which carry 46. To address this, scientists at Oregon Health & Science University developed a process called mitomeiosis, which mimics natural cell division and discards one set of chromosomes. This innovation allowed the creation of eggs with the correct chromosomal count for fertilization.

Lead researcher Shoukhrat Mitalipov described the achievement as the development of a third method of cell division, beyond mitosis and meiosis. In lab tests, 82 modified eggs were fertilized with sperm, but only 9% reached the blastocyst stage, a key milestone in embryo development. Most failed to progress beyond the 4- to 8-cell stage and showed chromosomal abnormalities. Despite low success rates, the study demonstrates that non-reproductive cells can be coaxed into egg-like behavior.

Implications for Infertility and Future Research

Reproductive specialists note that the technique could eventually transform how infertility and miscarriage are understood. Ying Cheong of the University of Southampton, who was not involved in the study, emphasized the potential for creating egg- or sperm-like cells for individuals with no other reproductive options. However, experts caution that clinical application remains a distant goal. Safety concerns and low developmental success mean that further research is essential.

Roger Sturmey of the University of Hull echoed this view, stating that while the concept is promising, it is far from ready for clinical use. The researchers themselves estimate that at least a decade of additional studies will be needed before human trials could be considered. Regulatory approval in the United States would also pose a significant hurdle. Until then, the technique remains confined to laboratory exploration.