An example of an idiom used in popular science writing:
"The telomerase complex is usually active in the germ cells, so that parents pass on long telomeres to their children. But in some of the families where there are mutations in the genes encoding the telomerase enzyme or the accessory RNA factor…each generation passes on shorter telomeres to its offspring. Because symptoms develop when the telomeres fall below a certain length, each successive generation is born nearer to the point where their telomere length falls over the cliff edge."
Nessa Carey (2015) Junk DNA. A journey through the dark matter of the genome. London: Icon Books Ltd.
Read about communicating science through idioms