Medicine Nobel Prize: Britain's Peter Ratcliffe jointly wins Nobel Medicine Prize with US researchers

Three researchers from the US and Britain on Monday shared the Nobel Medicine Prize for discoveries on how cells sense and adapt to oxygen availability, paving the way for new cancer treatments, the Nobel Assembly said.

William Kaelin and Gregg Semenza of the US and Britain's Peter Ratcliffe split the nine million Swedish kronor ($914,000, 833,000 euros) award.

"They established the basis for our understanding of how oxygen levels affect cellular metabolism and physiological function," the jury said, adding that their research has "paved the way for promising new strategies to fight anaemia, cancer and many other diseases."

The jury said the trio had identified molecular machinery that regulates the activity of genes in response to varying levels of oxygen, which is central to a large number of diseases.

"Intense ongoing efforts in academic laboratories and pharmaceutical companies are now focused on developing drugs that can interfere with different disease states by either activating, or blocking, the oxygen-sensing machinery," the jury said.

All animal cells use oxygen to convert food to usable energy.

"However, the amount of oxygen available to cells, tissues and animals themselves can vary greatly. This prize is for three physician scientists who found the molecular switch that regulates how our cells adapt when oxygen levels drop," Randall Johnson of the Nobel Assembly told reporters.

Kaelin, 61, works at the Howard Hughes Medical Institute in the US, while Semenza, 63, is director of the Vascular Research Program at the John Hopkins Institute for Cell Engineering.

Ratcliffe, 65, is director of clinical research at the Francis Crick Institute in London, and director of the Target Discovery Institute in Oxford.

Monday's announcement opened an unusual 2019 Nobel season in which two literature laureates will be crowned after a scandal postponed last year's award.

The Peace Prize will be awarded in Oslo on Friday, with speculation rife that Swedish teenage activist Greta Thunberg could win for her campaign to raise awareness about climate change.

Experts remain however divided on whether there is an actual link between armed conflicts and climate change.

Other names circulating are Ethiopian Prime Minister Abiy Ahmed, who clinched a peace deal with arch foe Eritrea, and NGOs such as Reporters without Borders and the Committee to Protect Journalists.

Prize for lithium batteries?

For Tuesday's Physics Prize, Swedish daily DN suggested it could go to quantum physics research, citing US scientist John Clauser, Alain Aspect of France, and Austria's Anton Zeilinger.

Ronald Hanson of the Netherlands could win for his work on quantum entanglement, SR said.

For the Chemistry Prize, American John Goodenough, who invented lithium batteries, could become the oldest ever winner of a Nobel, at the age of 97.

But it could also go to two women, Emmanuelle Charpentier of France and Jennifer Doudna of the US, for the gene-editing technique known as the CRISPR-Cas9 DNA snipping tool, a type of genetic "scissors" used to cut out a mutated gene in a human embryo and replace it with a corrected version.

Chinese-born American Feng Zhang also claims to have discovered the technique.

Sexual harassment scandal

Last year, the Swedish Academy which awards the Literature Prize was torn apart by a sexual harassment scandal that exposed deep conflicts among its 18 members. For the first time in 70 years, without a quorum to make key decisions, it postponed the 2018 Nobel by a year.

As a result, two literature laureates will be announced on Thursday, one for 2018 and one for 2019.

The Academy has spent the past year trying to address its issues and restore its honour, and is therefore seen to be steering clear of controversy in its picks.

Writers who have been making a buzz include Poland's Olga Tokarczuk, Kenya's Ngugi Wa Thiong'o, Ismail Kadare of Albania, Joyce Carol Oates of the US and Japan's Haruki Murakami, say critics questioned by AFP.

The Economics Prize will wrap things up on Monday, October 14. Three women have been mentioned as possible winners: Anne Krueger of the US for her work on international trade, Cuban-born American Carmen Reinhart for her work on public debt and growth, and French development aid economist Esther Duflo.