50 years ago, scientists were seeking the cause of psoriasis
Excerpt from the April 29, 1972 issue of Science News
![a photo of a hand scratching red scaly skin on a person's elbow. Only the person's torso and arms are in frame.](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2022/04/032122_ac_50ya-psoriasis_feat_rev.jpg?fit=1030%2C580&ssl=1)
Psoriasis affects 2 to 3 percent of people around the world. Itchy patches of scaly skin commonly show up on the elbows, knees, scalp, lower back and palms, among other areas.
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