Fermion mass matrices, textures and beyond
  The issue of texture specific fermion mass matrices have been examined briefly from the `bottom-up' perspective. In case no conditions are imposed, the texture ansatze leads to a large number of viable possibilities. However, besides textures, if in case one incorporates the ideas of `natural mass matrices' and uses the facility of Weak Basis Transformations, then one is able to arrive at a minimal finite set of viable mass matrices in the case of quarks. 
Manmohan Gupta, Priyanka Fakay, Samandeep Sharma, Gulsheen Ahuja
hep-ph