title: Genetics and molecular biology of the GHRH-GH-IGF-I axis.
abstract: In this paper, the genetics and molecular biology of the GHRH-GH-IGF-I (Growth Hormone Releasing hormone-Growth Hormone-Insulin like Growth Factor I) axis involved in the pathogenesis of short stature are reviewed. Short stature associated with GH deficiency is estimated to occur in about 1/4000-10,000 live births; 3-30% of cases affect first-degree relatives, suggesting a genetic aetiology. Identification of such molecular defects is very recent and dependent on new findings on the physiology of GHRH-GH-IGF-I axis: for example the pituitary-specific transcription factors and their mutations have only been described in the last few years. The epidemiological importance of the identified molecular defect depends on the level of the axis involved, but the prevalence of some of these genetic defects is probably underestimated. Time will tell what the practical relevance of these findings is and what the clinical features of the new mutations are; we will probably learn something more about the GHRH-GH-IGF-I axis: to date, no mutations have been reported regarding the GHRH gene or the IGF-I receptor.
authors.affiliation: Dipartimento di Pediatria, Università di Modena e Reggio Emilia.
authors.forename: S
authors.initials: S
authors.lastname: Bernasconi
authors.forename: A
authors.initials: A
authors.lastname: Bergomi
authors.forename: S
authors.initials: S
authors.lastname: Milioli
authors.forename: A
authors.initials: A
authors.lastname: Tirendi
authors.forename: G
authors.initials: G
authors.lastname: Mastronardi
authors.forename: S
authors.initials: S
authors.lastname: Mariani
authors.forename: B
authors.initials: B
authors.lastname: Predieri
authors.forename: M
authors.initials: M
authors.lastname: Ferrari
authors.forename: M
authors.initials: M
authors.lastname: Geti
authors.forename: L
authors.initials: L
authors.lastname: Livio
authors.forename: K
authors.initials: K
authors.lastname: Rossi
authors.forename: S
authors.initials: S
authors.lastname: Forese
authors.forename: L
authors.initials: L
authors.lastname: Iughetti
mesh_terms: D000328:Adult; D004392:Dwarfism / Q000235:genetics*; D005260:Female; D015870:Gene Expression / Q000235:genetics; D013007:Growth Hormone-Releasing Hormone / Q000235:genetics*; D019382:Human Growth Hormone / Q000235:genetics*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D008297:Male; D017354:Point Mutation / Q000235:genetics
chemical_list: D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013007:Growth Hormone-Releasing Hormone