We compute the GRB rates in different types of galaxies by performing a pop
ulation synthesis using the "Scenario Machine" code in the framework of mer
ging binary relativistic stars model. Our model predicts that similar to 1/
3 of GRB should occur in elliptical galaxies, and this fraction should incr
ease with the redshift. This fraction is comparable with the observed fract
ion of GRB without (detectable) X-ray afterglows.