Scientists created eggs from cells of an adult male mouse for the first time and obtained seven mice from two "fathers.
Researchers have been conducting experiments to create viable germ cells - eggs and sperm - from somatic cells of female and male mice for many years. Previously, they were able to turn female mouse skin cells into oocytes, and this time a group of scientists from several research centers in Japan decided to repeat a similar experiment with males.
To do this, they took skin samples from the tail of a male mouse and turned them into pluripotent stem cells. During this process, about six percent of all cells lost their Y chromosome, after which they were left with only one X chromosome out of a pair of sex chromosomes. Scientists had only to duplicate it using a special drug, which resulted in cells with a "female" set of two X chromosomes.
After that, the cells were used to create oocytes, which were fertilized with sperm from a second male mouse, and then the developing embryos were implanted into the uterus of a surrogate mother. Out of 630 attempts, only seven were successful: as a result, seven mice born of two males were born. The mice are healthy and, by all appearances, fertile.
It is not yet known whether this method will work on humans: there are too many differences between the mouse and human genomes. In addition, such research will inevitably encounter a wide range of problems, from low success rates (only about percent of the implanted eggs were able to develop into mice) to a whole host of ethical problems. For example, since the same person can be a donor of both eggs and sperm, what happens if we obtain an embryo from these two germ cells?
Nevertheless, the Japanese researchers' discovery offers tempting prospects for single men wishing to have a child. In addition, this method can help endangered animal species, from which too few males of different sexes have survived: now even a single surviving male can become the father of a new generation, if a suitable surrogate mother - a female of a related species - can be found.
