The invention relates to the breeding and selection of potatoes. The invention provides a potato plant or part derived thereof having at least one amf-allele said potato plant or part further provided with an increased capacity to store a protein as characterized by an increased protein content of its tubers. Furthermore, the invention provides a method for breeding and selecting a potato with an increased capacity to store a protein comprising crossing a first parent potato with at least one amf-allele with a second parent potato without an amf-allele, and selecting progeny for the presence of at least one amf-allele with a protein content a of its tubers higher than detected in said first parent or said second parent.