In our study, TTR tetramer concentration, different from total serum TTR concentration, in healthy donors was higher than that in E61K ATTRv amyloidosis patients, in previously reported serum TTR concentrations in the controls were statistically significantly higher than in the TTR V30M carriers in Swedish patients, which were in the same range as those in African-Americans carrying the TTR V122I allele (Buxbaum et al., 2010). Here, TTR is linked to amyloidosis.