Limited Ability for in Vitro Ternary Complex Formation (TCF) in Idiopathic Short Stature (ISS) Children Heterozygous Carriers (HC) for IGFALS Genetic Variants Associated with Low Levels of IGF-I, IGFBP-3 and ALS

SCAGLIA, PAULA; DOMENÉ, HORACIO; KARABATAS, LILIANA; KESELMAN, ANA; MARTÍNEZ, ALICIA; JASPER, HECTOR

Montevideo

Congreso; XXIII Reunion anual de la Sociedad Latinoamericana de Endocrinologia Pediatrica; 2012

Sociedad Latinoamericana de Endocrinología Pediátrica

Background: Near 10% of ISS children present IGFALSgene variants, 50% associated with low levels of IGF-I, IGFBP-3and ALS. We hypothesized TCF may be involved in the reductionof IGF-I levels. Objective: To determine TCF in ISS childrenHC or wild type (WT) for IGFALS gene with normal or low IGF-Ilevels. Methods: Patients were divided in three groups accordingto IGFALS genotype and IGF-I levels. TCF was determined bysize exclusion chromatography with and without the addition ofrhIGFBP-3 (6 ìg/ml). Results: Basal TCF levels did not differamong groups; after rhIGFBP-3 addition G1 showed significantlylower TCF and ÄTCF values. Basal TCF did not correlate with ALS(r=0.23, NS); it did after rhIGFBP-3 addition (r=0.66; P=0.0069).Conclusion: The limited ability for TCF in G1 suggests a causeeffectrelationship between the carrier status and the IGF-I deficiency,that could be responsible for their short stature.