CREB1 and metabolic disease: Although we were not able to directly examine PGC-1α transcription in our cohort, this CREB1 site is reported to be DM in metabolic disease (Sookoian et al., 2010) which suggests that DM sites at the PGC-1α promoter region and TSS in our ASD cohort could affect gene transcription and subsequently, mitochondrial biogenesis and function.