C.777delT & DF508

I think my son is the only one with this combination. Anyone else have c.777delT? He was diagnosed at birth with MI & sweat test of 112. He's 14 yrs old, no hospitalizations or major lung complications so far. Main issues are with digestion (since birth) & nasal polyps (onset age 12). The results of this second mutation read - c.777delT (frameshift): Not a previously reported CFTR to our knowledge but predicted to be deleterious. I'm assuming that means Class 2 but with the mildness of his disease so far it leads me to believe it's not? thoughts?
Source: Cystic Fibrosis DNA and Mutations Forum - Category: Respiratory Medicine Authors: Tags: DNA and Mutations Source Type: forums