Figure 4.

Time course of decrease in retinal function differs in P23H transgenic minipig founders. (A) Scotopic (rod) and (B) photopic (cone) full-field ERGs were recorded during the first 2 years of life under standard ISCEV protocols. The scotopic ERGs were evoked with a flash intensity of 0.01 cd · s · m⁻², after 20 minutes of dark-adaptation. The photopic ERGs were measured using flashes of 3 cd · s · m⁻² presented on a background of 30 cd · m⁻². The founders fell into two groups, based on both scotopic and photopic ffERGs, compared with WT littermates at 3 months of age (n = 3; dashed lines). Average b-wave amplitudes are plotted for the two transgenic founders who were moderately affected (63-1 and 51-1) and the four who were severely affected (53-1, 62-1, 63-2, and 64-1). Moderately affected founders had a later onset of rod and cone dysfunction and retained some degree of both rod and cone response through 12 months of age.