What Does the Franzini-Radicati Mass Relationship Imply about the Wigner Supermultiplet Symmetry?

Abstract
The Franzini-Radicati mass relationship between isobars is reexamined to find out whether it provides a good test of the Wigner SU(4) symmetry in nuclei. It is found that the mass ratio is an extremely insensitive function of the symmetry mixing.