TTR and autosomal dominant disease: ATTRv is an autosomal-dominant disease and over 130 transthyretin (TTR) variants have been identified that have ethnic and geographic distribution.6, 7, 8 Different TTR genotypes are associated with varying phenotypes.9, 10, 11 The correlation between genetic heterogeneity, variability in disease onset, and expression remains an active area of investigation.12