For the development of the new biomarkers using the technique of Mass-spectrometry 7, 5 ml EDTA blood or a dry blood spot filter card are taken. To proof the correct diagnosis of aTransthyretin-Related Familial Amyloidotic Polyneuropathy in those patients where up to the enrollment in the study no genetic testing has been done, sequencing of a Transthyretin-Related Familial Amyloidotic Polyneuropathy will be done.