Abstract
Purpose: :
OPA1
Methods: :
In addition to published husbandry and genotyping protocols, we carried out genotyping by allele-specific PCR for a potential confounding mitochondrial gene deletion, Nnt, (carried by all C57Bl/6). With selective breeding this deletion was removed from our line. Body weight, SHIRPA test, accelerating rotarod and OKN was carried out. Opa1 x Opa3 lines were crossed.
Results: :
Mean weights of all Opa1 male and female mice over 6 months age showed a trend towards lighter weight in Opa1+/- mice (WT 32.74g, SD=6.0; Het 29.47g, SD=2.7 ; p> 0.05). By 20 months of age there was a statistically significant difference between WT and Hets (WT 40.6g, SD=3.1; Het 28.77g, SD=2.44; p< 0.05). 12 month Opa1+/- showed reduced mean performance on rotarod (WT 92s, SD=10; Het 70s, SD=20.9; p=0.05). Rotarod testing at 20 months was discontinued since grossly obese wild type mice were unable to perform the test and act as controls. Opa1 x Opa3 cross revealed no evidence on SHIRPA or OKN testing of increased severity of phenotype (G2).
Conclusions: :
Opa1+/- mice are lighter than WT age and sex matched controls. Rotarod testing confirms a subtle neuromuscular defect in Opa1+/- mice in line with previous SHIRPA testing. Opa1+/- mice on a mutant Opa3+/- background showed no evidence of more severe phenotype.
Keywords: neuro-ophthalmology: optic nerve • genetics • gene/expression