Gauge-Yukawa Unification (GYU) yields a functional relation among the gauge and Yukawa couplings, and it may follow from the usual Grand Unification if it is supplemented with some additional principles. Postulating the principles of finiteness and reduction of couplings, we have achieved Gauge-Yukawa Unification in various supersymmetric unified models leading, among other things, to interesting predictions on the top quark mass.
@article{arxiv.hep-ph/9509434,
title = {Gauge-Yukawa Unification},
author = {Jisuke Kubo and Myriam Mondragon and George Zoupanos},
journal= {arXiv preprint arXiv:hep-ph/9509434},
year = {2007}
}