Or for the British out there a full stop. Or from the linked page:
"A nonsense mutation is a point mutation that introduces a premature stop codon into the part of the gene that encodes a protein. A stop codon is like a period at the end of a sentence: it instructs the ribosome to stop making the protein. So if a mutation leads to an early stop codon, only part of the protein will be made. 'Half-baked' proteins that result from nonsense mutations are often nonfunctional or defective."
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.