Basically half of the main cast (7 out of 14 or 15 depending on how you count) have died below life expectancy for their birth year. The causes of their deaths are all different or at least had very different comorbidities. That is really weird.

This is the first thing I thought of when I saw the headline.

Here they are, from the "starring" field of the B5 Wiki page:

   60 Michael O'Hare
   60 Jerry Doyle
   65 Mira Furlan
   44 Richard Biggs
   63 Stephen Furst
   59 Andreas Katsulas
   60 Jeff Conaway

Also, not starring but great in a bit role:

   49 Tim Choate

> 49 Tim Choate

Zathras died!? Oh man!