The research team used yeast chromosome No. 3 as the model for their biochemical stitchery. Pins and white diamonds in the illustration represent "designer changes" not found in the usual No. 3; yellow stretches represent deletions.
The rupture of a weakened portion of blood vessel (the dark blue spot in this brain scan of a 68-year-old woman) can prompt bleeding and death of brain tissue — a stroke.
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