ATP7B peptide concentration analysis can provide clear results where
ceruloplasmin results and genetic analysis are ambiguous. Patients with
significantly (A), moderately (B), and normal (C) Cp were readily identified.
ATP7B concentrations are reduced regardless of variant status including in
patients with two pathogenic or likely pathogenic variants (D), at least one VUS
(E), or where no second variant was found (F). Cp = Ceruloplasmin. Dotted Lines
represent peptide diagnostic cutoffs. Patients with liver copper above (G) or
below 256 ug/g (H) are shown. In three samples from non-WD patients with
elevated liver copper, ATP7B concentrations are normal (I).