There is a strong correlation between the formation of genitals and limbs, the Boston Globe reports, citing a study conducted by researchers from the Harvard Medical School and published in the journal Nature.
Researchers examined the genetic processes that take place during the development of embryos in various animals, and also performed complex cell-transplant surgeries to see if they could get genitals to grow elsewhere. They partially succeeded — causing genital-like buds to form in a chicken embryo — by using the cells that generally form hind limbs.
Patrick Tschopp, the study’s lead author and a postdoctoral researcher at Harvard, pointed out that babies born with poorly formed limbs often also possess poorly formed genitalia. “We knew there was some sort of genetic link between the two, and this could provide some information about where these genetic links are,” he said.