Two unrelated Italian families affected by hereditary amyloidosis are described. Molecular genetic characterization demonstrated different mutations of the transthyretin gene. In all patients belonging to the TTR Ala 49 family the vitreous body, the heart and the peripheral nervous system were massively infiltrated by amyloid matter. In the TTR Pro 36 family vitreous opacities were the long-standing isolated manifestations of the disease. Two different patterns of vitreous deposits can be observed in these two families. The authors' data support the hypothesis that different pathological transthyretin proteins may have different affinity for the connective tissue in the vitreous.