Fig. 6.

Truncating mutations in the polycystic kidney and hepatic disease 1 (PKHD1) gene increase cell culture medium acidification. A: at day 3 (D3), PKHD1 gene mutations had no significant effect on cell culture medium acidity, reflected by absorbance at 560 nm (Abs₅₆₀, maximum for phenol red; P = 0.1553). B: by day 8 (D8), the effect of PKHD1 mutation on increase in cell culture medium acidity, reflected by Abs₅₆₀, was significant (P < 0.0001). C: increase in culture medium acidity was greater overall in cell clones with PKHD1 truncating mutations over time (reflected by decrease in Abs₅₆₀, P < 0.0001) when 6 values from D3 to D8 were used for trajectory analyses. D: each of the PKHD1 truncating mutations showed a greater increase in acidity over time than WT (all P < 0.0001). The 626* label designates the PKHD1 p.K626_M627del clone that was not included in these statistical analyses; however, when it was included, results of the above analyses were nearly identical.