It was the drugs and lifestyle, no doubt. And the inability of anyone in her circle to pull her out of her decline.

But the shocking death Saturday of Amy Winehouse, a singer of such great power and promise, also puts her in the realm of the rock stars who died at age 27.

What is it about that age, creeping toward 30, that so many rock stars cannot pass? It was the year that Jimi Hendrix, Janis Joplin and Jim Morrison all died in quick succession in 1970. Twenty seven is also when Kurt Cobain died.

Brian Jones died at 27 and so did that inspiration to his band the Rolling Stones, bluesman Robert Johnson. Twenty-seven is when Ron “Pigpen” McKernan of the Grateful Dead died, and when Pete Ham of Badfinger did.

Kristen Pfaff, bassist of Hole, O.D.’d at 27 and Mia Zapata of another Seattle group, the Gits, was found murdered at 27.

It’s more than the year that killed all of them. But the coincidence may mean a little closer care to musicians as they reach that age.