Description
We discovered a rare missense mutation in NR1H4 (R436H), which encodes the farnesoid X receptor (FXR), associating with lower levels of total cholesterol in the Icelandic population. To explore the effects of R436H we used CRISPR-Cas9 to generate homozygous NR1H4 R436H and NR1H4 knockout human iPSC lines which we differentiated to hepatocytes. Hepatocytes were treated with an FXR agonist for 24 hours and transcript abundance measured by RNA-seq. The global response to FXR activation in NR1H4 R436H cells was very similar to that of wild-type cells showing that it is not a loss-of-function mutation. However, we did observe subtle gene expression differences compatible with an effect on lipids when we compared R436H agonist treated hepatocytes to wild-type agonist treated hepatocytes. Overall design: RNA-seq was performed on wild-type, NR1H4 knockout and NR1H4 R436H iPSC-derived hepatocytes treated with FXR agonist GW4064.