CYCS and Marfan syndrome: Compared with healthy control samples, TAA samples from MFS patients showed significantly lower levels of mRNA of TFAM and mtDNA (Figure 3B), as well as reduced transcription of genes that encode mitochondrial complexes (MT-ND1, SDHA [succinate dehydrogenase complex, subunit A], SDHB [succinate dehydrogenase complex, subunit B], CYCS [cytochrome complex], MT-CO1, and MT-ATP6 [mitochondrially-encoded ATP synthase membrane subunit 6]) or are involved in mitochondrial function (PPARA, PPARG, and PPARG1A; Figure 3C and 3D).