The Human Growth Hormone Gene Locus: Structure, Evolution, and Allelic Variations

Heribert Hirt, Judy Kimelman, Morris J. Birnbaum, Ellson Y. Chen, Peter H. Seeburg, Norman L. Eberhardt, Andrea Barta

Research output: Contribution to journalArticle

107 Scopus citations

Abstract

Genomic clones containing the closely related genes for human growth hormone (hGH) and chorionic somatomammotropin (hCS) were obtained from genomic bacteriophage λ and cosinid libraries. The entire GH/CS chromosomal locus was reconstructed utilizing overlapping restriction fragments characterized from the isolated clones. The hGH/hCS locus contains two GH genes and three CS genes spanning 48 kb of DNA in the order: 5′-(hGH-l/hCS-5/hCS-l/hGH-2/hCS-2)-3′, confirming analysis of cosmid clones obtained from a different human library (Barsh et al., 1983). To complete the characterization of the hCS genes, the nucleotide sequence of the hCS-5 gene was determined. Sequence analysis revealed a mutation of the 5′ splice site at the exon II-intron B boundary, suggesting that the hCS-5 gene is a pseudogene. The nucleotide sequence of an allelic variant of the hCS-2 gene was determined and found to contain a single amino acid substitution and the deletion of a single codon. The hGH/hCS gene locus was further characterized by the localization of at least 27 Alu-type repetitive sequences and identification of three unique sequences in the vicinity of several hGH and hCS genes which define the probable breakpoints of the evolutionary duplication units. These data, combined with the nucleotide sequences of all five GH and CS genes, indicate that the hGH/hCS gene locus has evolved by duplication mechanisms. Evidence for the occurrence of at least one gene conversion event involving the hCS-1 gene precursor and the hCS-2 gene was found, indicating that the hGH/hCS gene locus has evolved by concerted mechanisms. The structure of the hCS genes is discussed in light of recent studies of CS genes from other mammalian species.

Original languageEnglish (US)
Pages (from-to)59-70
Number of pages12
JournalDNA
Volume6
Issue number1
DOIs
StatePublished - Feb 1987

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Genetics

Fingerprint Dive into the research topics of 'The Human Growth Hormone Gene Locus: Structure, Evolution, and Allelic Variations'. Together they form a unique fingerprint.

  • Cite this

    Hirt, H., Kimelman, J., Birnbaum, M. J., Chen, E. Y., Seeburg, P. H., Eberhardt, N. L., & Barta, A. (1987). The Human Growth Hormone Gene Locus: Structure, Evolution, and Allelic Variations. DNA, 6(1), 59-70. https://doi.org/10.1089/dna.1987.6.59