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The news this week has centered on the tragic plight of Dwight Clark, but at least a dozen other NFL players have suffered from the fatal neurodegenerative disease ALS.
Seven had died from Lou Gehrig’s disease by the time Clark passed away Monday at age 61 — including three members of the 1964 49ers.
The high incidence of amyotrophic lateral sclerosis among the professional football community has led researchers to explore links to the game.