American Barry Sharpless on Wednesday became only the fifth person ever to win a second Nobel Prize, two decades after being awarded his first.

AFP looks at the four other people who received the illustrious award twice for their services to mankind:

– Marie Curie (1903, 1911) –

The mother of modern physics was the first woman ever to win not one, but two, Nobel prizes for her seminal discoveries in physics and chemistry.

Born Maria Sklodowska in Poland, Curie moved to Paris as a student and is famed for having isolated the elements of polonium and radium as well as for promoting radium to alleviate suffering.

In 1903, she was awarded the Nobel Prize in Physics, along with her husband Pierre Curie and French physicist Antoine Henri Becquerel for their research into spontaneous radiation.

A second Nobel followed in 1911, this time for chemistry, when Curie was honoured alone for her work on radioactivity.

– Linus Pauling (1954, 1962) –

Linus Pauling, the US chemist who posited that huge doses of vitamin C can ward off the common cold, is the only person to have been awarded two unshared Nobel Prizes – the 1954 Nobel Prize in Chemistry and the 1962 Nobel Peace Prize.

Pauling won his first Nobel in 1954 for his work in molecular chemistry, particularly in the field of proteins and anti-bodies.

His second award came eight years later in 1962 was in recognition for his campaigning against nuclear testing.

– John Bardeen (1956, 1972) –

US engineer John Bardeen shared the Nobel Prize in Physics twice.

In 1956, he and two colleagues at Bell Labs, William Shockley and Walter Brattain, won for inventing the transistor, which revolutionised the field of electronics by leading to smaller and cheaper radios, calculators and computers, amongst other objects.

In 1972, he picked up his second Nobel for developing the BSC-theory of superconductivity, with fellow American physicists Leon Cooper and John Robert Schrieffer.

– Frederick Sanger (1958, 1980) –

British biochemist Frederick Sanger, dubbed the father of genomics, was the only person to win the chemistry Nobel twice.

Sanger was the sole winner of the prize in 1958 for his work on the structure of proteins, notably insulin, and then shared it with two others, Paul Berg and Walter Gilbert of the United States, in 1980 for pioneering developments in DNA sequencing that are still being used today.

His work allowed long stretches of DNA to be rapidly and accurately sequenced and was central to the Human Genome Project’s mammoth achievement in mapping more than three billion units of human DNA.

– ICRC and UNHCR –

Two organisations have won multiple Nobel Peace Prizes.

The International Committee of the Red Cross won in 1917, 1944 and 1963 and the Office of the UN High Commissioner for Refugees won in 1954 and 1981.

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