In 2013, scientists discovered a new way to precisely edit genes — technology called Crispr that raised all sorts of enticing possibilities. Scientists wondered if it might be used to fix hereditary diseases, for example, or to develop new crops.

One of the more intriguing ideas came from Kevin M. Esvelt and his colleagues at Harvard University: Crispr, they suggested, could be used to save endangered wildlife from extinction by implanting a fertility-reducing gene in invasive animals — a so-called gene drive.

Continue reading “‘Gene Drives’ Are Too Risky for Field Trials, Scientists Say” →

For centuries, skin color has held powerful social meaning — a defining characteristic of race, and a starting point for racism.

“If you ask somebody on the street, ‘What are the main differences between races?,’ they’re going to say skin color,” said Sarah A. Tishkoff, a geneticist at the University of Pennsylvania.

On Thursday, Dr. Tishkoff and her colleagues showed this to be a profound error. In the journal Science, the researchers published the first large-scale study of the genetics of skin color in Africans.

Continue reading “Genes for Skin Color Rebut Dated Notions of Race, Researchers Say” →

Earlier this year, my colleagues at The New York Times started to report on a medical mystery that has turned into an international standoff. American diplomats in Cuba have fallen ill with a variety of perplexing symptoms, including — reportedly — some that might denote mild brain injury.

Continue reading “What’s a Science Reporter to Do When Sound Evidence Isn’t Sound?” →

A scientific enigma lies at the heart of a strange confrontation between the United States and Cuba.

According to the State Department, nearly two dozen diplomats at the American Embassy in Havana have been stricken with a variety of mysterious medical symptoms, including hearing loss and cognitive difficulties.

After concluding that staffers were the victims of a stealth attack, the department withdrew nonessential personnel from Havana and issued an advisory urging Americans not to visit. On Tuesday, the Trump administration expelled 15 Cuban diplomats from the United States.

Continue reading “A ‘Sonic Attack’ on Diplomats in Cuba? These Scientists Doubt It” →

In July, scientists reported that a strange protein courses through the veins of pregnant women. No one is sure what it’s there for.

What makes this protein, called Hemo, so unusual is that it’s not made by the mother. Instead, it is made in her fetus and in the placenta, by a gene that originally came from a virus that infected our mammalian ancestors more than 100 million years ago.

Hemo is not the only protein with such an alien origin: Our DNA contains roughly 100,000 pieces of viral DNA. Continue reading “Ancient Viruses Are Buried in Your DNA” →