# How to set equal distances between axes ticks irrespective of number of points I plot in a ggplot?

how can I set an equal distance between the ticks of axes in a ggplot irrespective of the number of items I plot?

For example I want to have the kind of plot below from Seurat's DotPlot function from this nature paper

Instead of the second plot below (still with Seurat's DotPlot function) where the spacing on the x-axis varies with respect to the number of genes plotted.