Analysis of calretinin+ interneurons revealed a significant main effect across all groups in the occipital, frontal and temporal cortices (Kruskal–Wallis, P < 0.0001), with post hoc analyses demonstrating significantly decreased levels of NDUFB8 and COXI within calretinin+ interneurons from patients with Alpers' syndrome relative to controls (P < 0.0001) (Figure 4B,C). This evidence concerns the gene CALB2 and Alpers syndrome.