Fig. 1

Unadjusted correlation matrix between thyroid hormones (FT3, FT4, TSH), mtDNA methylation (MT-RNR1, D-loop), and mtDNA content. Numbers represent Pearson correlation coefficients and only the colored boxes are significant correlations at p-level < 0.05 (red: positive significant correlation; blue: negative significant correlation; blank: not-significant)