Genetic mapping of the human pituitary-specific transcriptional factor gene and its analysis in familial panhypopituitary dwarfism

We have analyzed the human pituitary-specific transcription factor (Pit-1) gene using PCR amplification of DNA fragments that span intron III and contain portions of exons III and IV. A PCR restriction fragment length polymorphism (PCRFLP) was detected in intron III by RsaI digestion, which was used to assign the human Pit-1 locus to chromosome 3p by linkage analysis of the CEPH panel. Analysis of corresponding Pit-1 segments from six nonrelated probands with familial panhypopituitary dwarfism (FPD) did not reveal any alterations in size and co-segregation of Pit-1, or a tightly linked microsatellite marker (D3S1559), and FPD was excluded in all six kindreds. Our data (1) assign Pit-1 to human chromosome 3p by linkage, (2) provide a PCRFLP and identify a variety of tightly linked markers, for analysis of FPD, and (3) exclude Pit-1 defects as the basis of at least one form of FPD.