MacTel patients have distinct SL alterations compared to patients with HSAN1. (A) Volcano plot comparing HSAN1 patients with MacTel, to HSAN1 patients without MacTel. Dashed line represents p = 0.05. Only metabolites below this threshold are labeled and coloured by metabolite class. (B) Depiction of the log2 fold change of 1-deoxysphingolipids in MacTel only, HSAN1 only, and HSAN1 patients with MacTel, compared to Controls. Tiles indicate the mean log fold change in abundance between each cohort and controls. Black points indicate FDR-significant changes. Red colors indicate increased relative abundance, and blue colors indicate decreased abundance. (C) Scaled abundance of averaged dihydroxyceramide levels in Controls, MacTel only, HSAN1 only, and HSAN1 patients with MacTel. Center line indicates the median and box limits indicate the 25th and 75th percentiles. (D) Depiction of the log2 fold change of d18:2 ceramides in MacTel only, HSAN1 only, and HSAN1 patients with MacTel, compared to Controls. Tiles rendered as for panel B. (E) Depiction of the log2 fold change of sphingomyelins in MacTel only, HSAN1 only, and HSAN1 patients with MacTel compared to Controls. Tiles rendered as for panel B. (F) Scaled abundance of averaged sphingomyelin levels in Controls, MacTel only, HSAN1 only, and HSAN1 patients with MacTel. Center line indicates the median and box limits indicate the 25th and 75th percentiles. (G) Summary of the amino acid and SL alterations in MacTel, HSAN1, and HSAN1 patients with MacTel compared to Controls. Red indicates increased, and blue indicates decreased abundance. Abbreviations: doxDHCer, deoxydihydroceramide; doxCer, deoxyceramide; DHCer, dihydroceramide; Cer, ceramide; Gluc/Gal-Cer or GlucCer, glucosyl/galactosyl-ceramide; Lact-Cer, lactosyl-ceramide; SM, sphingomyelin.