The present invention relates to the genes involved in the biosynthetic pathway for sesquiterpenes of SB type (alpha-santalene, epi-beta-santalene, cis-alpha-bergamotene, trans-alpha-bergamotene and endo-beta-bergamotene,) and for the precursor thereof, Z,Z-farnesyl diphosphate (Z,Z-FPP), involving a Z,Z-FPP synthase and a sesquiterpene SB synthase, and to the uses thereof for producing sesquiterpeniques compounds of SB type.