Photograph 51

It might be the most egregious slight in modern science.

By the early 1950s, we knew that whatever it was that parents passed along to their offspring was locked inside a mysterious chemical called DNA. The race was on to discover the structure of the DNA molecule. 

At Cambridge University, James Watson and Francis Crick were leading the pack. Trying (and failing) to build a model of a DNA molecule, Watson and Crick were close, but not yet successful. 

Nearby at Kings College London was the laboratory of Maurice Wilkins and Rosalind Franklin. Wilkins and Franklin were using x-ray photography to look at images of DNA molecules. Rosalind Franklin produced a particularly stunning photo of DNA, known as “Photograph 51”.

Photograph 51, called the “most important photo ever taken”, provided groundbreaking insights into DNA and modern genetics. 

Without her knowledge or consent, Maurice Wilkins showed Rosalind Franklin’s “Photograph 51” to James Watson. Watson later recalled that when he saw the photo, “my mouth fell open and my pulse began to race.”

Franklin’s physical image of DNA was the final piece of the puzzle. The now famous double-stranded twisted ladder shape of DNA was deciphered, thanks to Franklin’s photo and Watson and Crick’s mathematics. 

The discovery of the structure of DNA opened the door to modern genetics. Medicine, agriculture, and biotechnology leapt forward, and the 21st century is set to be the century of genetics. 

In 1962, the Nobel Prize for Medicine/Physiology was awarded to James Watson, Francis Crick, and Maurice Wilkins. 

In a slight still debated to this day, Rosalind Franklin was not included. 

The Nobel committee only awards the prize to living recipients, and Rosalind Franklin died four years earlier of ovarian cancer, at the age of 37.

Between 1901 and 2020, the Nobel Prize in Chemistry has been awarded to only seven women, and never to more than one at a time. 

For the first time in history, the 2020 Nobel Prize in Chemistry was shared by two women, Jennifer Doudna (U.C. Berkeley) and Emmanuelle Charpentier (Max Planck Unit for the Science of Pathogens, Berlin).

Jennifer Doudna and Emmanuelle Charpentier

Doudna and Charpentier were intrigued by an ancient immune response in bacteria. When a virus infects certain bacteria, the bacteria react by chopping up the DNA of the invading virus. The bacteria keep pieces of the chopped up viral DNA and incorporate it into their own DNA, kind of like a genetic “mugshot” of the invader. If the virus attacks again, the bacteria send chemical “scissors” to cut up the viral DNA at the precise location of the “mugshot” DNA. 

This bacterial immune response is named for the viral mugshots: CRISPR (pronounced like the drawer in the fridge where you store your vegetables).

Doudna and Charpentier retooled CRISPR and used it to edit DNA in living cells with incredible precision and accuracy.

Already their discovery has impacted plant breeding and agriculture. Probably most exciting, however, are the possibilities for treating genetic diseases. 

Meet Victoria Gray. 

Victoria, a wife and mom of three, was born with sickle cell disease, a devastating genetic disorder. One single mutation in the DNA of people with sickle cell disease turns their red blood cells into deformed, sickle-shaped cells. The misshapen cells get stuck in blood vessels, resulting in damaged organs, debilitating pain, and often premature death.

The gene that causes sickle cell disease produces a defective form of hemoglobin, the protein in red blood cells responsible for carrying oxygen. There is another kind of hemoglobin made by babies before birth called “fetal hemoglobin”. After a baby is born, a gene called BCL11A turns on. BCL11A tells blood cells to stop making fetal hemoglobin and start making adult hemoglobin. In people like Victoria with sickle cell disease, adult hemoglobin is defective. 

One year ago, doctors removed cells from Victoria’s bone marrow. Using CRISPR technology, the BCL11A gene was cut out, restoring production of fetal hemoglobin. 

As of June 2020, 46% of the hemoglobin in Victoria’s system is fetal hemoglobin, enough to significantly reduce her pain and hospitalizations. 

The doctor in charge of Victoria’s treatment had this to say: “She is functioning as somebody who does not have sickle cell disease. I believe this is absolutely, totally transformative therapy.” 

CRISPR therapy holds promise for other genetic diseases, including beta thalassemia, cystic fibrosis, and some cancers. 

“It’s a blessing,” Victoria said. “It gave me hope when I was losing it. So I feel joy, you know, knowing that there is hope.”

Congratulations to Drs. Doudna and Charpentier for the 2020 Nobel Prize in Chemistry. 

I think Rosalind would be proud.

And as You speak
A hundred billion creatures catch Your breath
Evolving in pursuit of what You said
If it all reveals Your nature so will I

(Hillsong United “So Will I“)

Here I am with an actual model built by Watson and Crick (The Science Museum, London)

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