A generalization of the well-known Geogi-Jariskog relation (m(mu)/m(tau)) =
3(m(s)/m(b)) to neutrinos is found in the context of SO(10). This new rela
tion is (m(nu mu)/m(nu tau)) = 16(m(c)/m(t)), which is consistent with pres
ent data, assuming the Mikheyev-Smimov-Wolfenstein solution to the solar ne
utrino problem.