The single-gene mutations directly responsible for early-onset Alzheimer's disease do not seem to be involved in late-onset Alzheimer's, and researchers have not found a specific gene that causes the late-onset form of the disease.
The NFLâs worst defense in 2015 are expected to be the Atlanta Falcons, Jacksonville Jaguars, Tennessee Titans, Chicago Bears and Tampa Bay Buccaneers (not necessarily in that order).
Anchored by Mean Joe Greene, the Steel Curtain helped Pittsburgh win four Super Bowls. Check out our list of the 10 best NFL defenses of all time, and then see how our readers ranked their choices for the most dominating defensive unit. And be sure to vote in the poll to crown the No. 1 defense ever. 1. 1976 Pittsburgh Steelers. The Steelers defenses of the 1970s are legendary, but the 1976 unit was the best (slightly better than the '75 squad). Here's why: 28. That's how many points the Steel Curtain surrendered in the last nine games of the season.