Age-dependent increase in amyloid deposition in CMV-λ6 mice. Proportion of transgenic mice at various ages with amyloid deposits in stomach sections detected by Congo red staining of a single section of stomach. Groups included mice that were < 6 months (n = 19), 6-12 months (n = 18), 12-18 months (n = 54), 18-23 months (n = 29), and 24-30 months of age (n = 6).