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. The transition metals — including iron, ...

The team first created mice that lacked a key iron accumulation gene in the gonadal cells of XY embryos during the period of sex determination. These embryos had higher levels of DNA methylation, ...

Scientists in Japan and Australia have shown that iron deficiency during pregnancy can cause a complete sex reversal in genetically male mice carrying XY chromosomes, leading them to develop ovaries.

Photograph of offspring born to iron chelator-treated mothers during pregnancy. Left, normally developed XY male animal; middle, intersex-phenotype XY animal; right; completely feminized XY animal.

THE CONVENTIONAL way of making babies is no secret: a father produces a sperm which, when it comes into contact with a mother’s egg, gives rise to an embryo containing genetic material from both ...