  Using a sample of 215 supernovae (SNe), we analyse their positions relative
to the spiral arms of their host galaxies, distinguishing grand-design (GD)
spirals from non-GD (NGD) galaxies. Our results suggest that shocks in spiral
arms of GD galaxies trigger star formation in the leading edges of arms
affecting the distributions of core-collapse (CC) SNe (known to have
short-lived progenitors). The closer locations of SNe Ibc vs. SNe II relative
to the leading edges of the arms supports the belief that SNe Ibc have more
massive progenitors. SNe Ia having less massive and older progenitors, show
symmetric distribution with respect to the peaks of spiral arms.
