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This is the page for this CASP10 refinement target:
Note that the organizers give us this as a hint:
"N-term res. 1-4 are disordered in the native structure and removed from the starting model. Starting GDT_TS=84."
So, the first 4 residues have been deleted.
GDT_TS=84 essentially means that 84% of the model superimposes correctly onto the native structure: