DIRAS1 expression. (A) The increase in the expression of the DIRAS1 transcript by age was observed when comparing six different age points in the frontal cortex (the ages of 2 mo, 5 mo, 23 mo, 4 y and 10 mo, 5 y and 3 mo, and 9 y, n = 1 in each). (B) The stability of the DIRAS1 transcript was studied in the frontal cortices of age-matched (24- and 23-mo-old) case (RR, n = 1) and control (Great Dane, n = 1) dogs by a quantitative PCR. The result suggests a modest decrease in the stability of the mutant transcript. The error bars refer to variance in experimental triplicates (SD < 0.13 in each). YWHAZ and GADPH were used as loading controls in quantitative PCR.