PharmGKB Schema Documentation: <proteinChange>

proteinXref	A cross-reference to the protein this proteinChange contributes to. If aminoAcidPosition is defined in any proteinChange subelement, this element is required as the aminoAcidPosition will be based on the cross-referenced protein.
aminoAcidPosition	The position of the amino acid this proteinChange codes for on the protein sequence defined in the parent element.
referenceAminoAcid	The reference amino acid. The reference amino acid sequence must be composed of the standard IUB-IUPAC amino acid symbols and `-`'s (to denote a deletion).
variantAminoAcid	The variant amino acid. The variant amino acid sequence must be composed of the standard IUB-IUPAC amino acid symbols and `-`'s (to denote a deletion).

Content validation performed on this element:

The aminoAcidPosition must lie on the sequence of the protein as cross-referenced by proteinXref.
The referenceAminoAcid must not match the variantAminoAcid.

cannot be filled in by submitters:
required when defining a new element:
at least one required when defining a new element:
only one allowed, required when defining a new element:
details ...