Dose-response relationships for 4 short-chain fatty acids.

Butyric (A), propionic (B), pentanoic (C), and hexanoic (D) acid are shown. ○ indicates values from experiments performed on different days. • indicates mean values. All 4 short-chain fatty acids increase the γ^F/γ^F+2β^R ratio. Higher levels of γ^F/γ^F+2β^R ratios were observed in propionate- and pentanoate-treated cells, though at higher concentrations than butyrate. Hexanoate was the weakest γ-globin gene inducer among the short-chain fatty acids tested.