The human gene for parathyroid hormone (PTH) was chromosomally mapped using human-rodent hybrids and Southern filter hybridization of cell hybrid DNA. A recombinant DNA probe containing human PTH cDNA insert (pPTHm122) hybridized to a 3.7-kb fragment in human DNA cleaved with the restriction enzyme EcoRI. By correlating the presence of this fragment in somatic cell hybrid DNA with the human chromosomal content of the hybrid cells, the PTH gene was mapped to the short arm of the chromosome 11.