Fig. 1

Longitudinal FDG and PiB positron emission tomographic (PET) scans for brothers A and B with corresponding uptake values in SUVr(/pons) and z-scores. The two upper rows of the figure represent the longitudinal FDG and PiB PET scans for brother A during repeated follow-up examinations. The year of each examination is noted at the top of each column. The lower two rows of the figure represent the corresponding longitudinal FDG and PiB PET scans for brother B. The values included in the tables are standardized uptake value ratios (SUVr) for the ROIs in the study, with the pons used as a reference region, as well as the corresponding z-score values with respect to the control group of noncarriers. FDG z-score values less than − 1.96 and PiB z-score values greater than + 1.96 are indicated in bold italic type. FDG [¹⁸F]fluorodeoxyglucose, GM Gray matter, PiB [¹¹C]Pittsburgh compound B, SUVr Standardized uptake value ratio