The mutation means that Duffy receptor proteins are not made in red cells.

ECONOMIST: AIDS

Dr He and his colleagues looked at the genes of airmen who classified themselves as black and found that the ones infected with HIV were more likely to lack red cells bearing the Duffy receptor than chance would suggest.

ECONOMIST: AIDS

After blood passes into the mosquito gut, the parasites quickly turn into male and female forms the gametes and emerge from their hiding place inside the red blood cells to mate.

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When a blue light is applied to the area, it activates the drug and shows any abnormal cells as red.

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At sunset, the sun appears red (the blue light has been scattered out of that image, too), so the cells of the eye that detect red are overloaded and incapable of registering weaker red signals.

ECONOMIST: In a flash

These tiny red devils crawl into bee brood cells, where they feast on larvae.

FORBES: Life

The vast majority of colorblind people have trouble seeing red or green, due to a genetic defect in the color-sensing cells, called cones, at the back of the eye.

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The causes are not known but probably include a combination of inherited bad genes, bad diet (too much fat and red meat, too few vegetables) and random genetic errors that occur as cells divide.

FORBES: Men, Cancer, & Hope

Meat, especially red meat, being the most readily assimilable protein, becomes a banquet for cancer cells.

FORBES: Connect

The treatment starts with a red wine and vitamin E exfoliant applied all over the body to scrub away dry skin cells.

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LaserMotive uses special cells made with arsenic and gallium, which are better able to capture the near-infra-red wavelengths of its laser beam.

ECONOMIST: Monitor