Scientists have raised the first viable mouse with two male parents into adulthood after editing imprinting genes.

The experiments show that changes in iron levels can lead male mammalian embryos to develop female sex characteristics, regardless of their genetics.

Researchers at Shanghai Jiao Tong University have produced fertile adult mice from embryos constructed entirely with male ...

In mice, a lack of maternal iron impairs an iron-dependent enzyme that activates the male sex-determining gene, causing some XY embryos to develop ovaries.

Human development is a beautiful, complex process. Beginning from just two germ cells, the cells divide and double until an entire organism is developed in just under a year.

Okashita N, et al. Maternal iron deficiency causes male-to female sex reversal in mouse embryos. Nature. 2025. Livernois AM, et al. The origin and evolution of vertebrate sex chromosomes and dosage ...

Nucleus says it can test IVF embryos not just for well-known specific genes that have a high chance of illnesses like breast cancer, but also for appearance — sex, height, hair color, eye color ...

U.S. Shouldn’t Have Revoked Harvard Frog Embryo Researcher’s Visa, Judge Says. Government says Kseniia Petrova tried to illegally smuggle the specimens into the country. By .

In this week's PEOPLE cover story, Olivia Munn reveals she and husband John Mulaney are still talking about whether they'll explore having another daughter with their last frozen female embryo.

During embryonic development, thousands of cells divide and move as one. Understanding the mechanisms that coordinate this collective behavior remains a significant challenge in biology and the ...

Harvard University researcher Kseniia Petrova, 30, smiles after being released on bail from federal custody at the John Joseph Moakley United States Courthouse on Thursday, June 12, 2025, in Boston.