Approximately more than 120 transthyretin mutations are known whose variation in clinical presentation is heterogeneous, as the course of disease onset depends on genetic variation and level of penetrance. It is little known in Ecuador, and some of the reported cases; suggest to the family tree analysis that they come from a province that is possibly considered endemic. The main objective is to carry out a descriptive cross-sectional analysis on the presentation of transthyretin amyloidosis in families carrying the p.Ser43Asn gene from the index case identified.