<p>Disclosed is a DNA fragment comprising a base sequence coding for a peptide occurring in human atrium cordis and having diuretic action or a precursor of the peptide, plasmids containing the DNA fragment, micro-organisms transformed with the plasmid, and a process for production of the peptide using the transformant.</p><p>Also disclosed is a new peptide consisting of 126 amino acids occurring in human atrium cordis and a precursorthe- reof. The peptide has notable diuretic action and hypotensive or antihypertensive actions.</p>
