The role of the genetic study of growth hormone genetic mutations for diagnosing syndrome of biologically inactive growth hormone in children

Abstract

Aim. To determine the role of the genetic study of mutations in growth hormone gene for diagnosing syndrome of biologically inactive growth hormone (GH) to clarify its form and the purpose of pathogenetic treatment. Materials and methods. There were examined 153 children (61 girls and 92 boys) aged 3-10 years with growth retardation more than minus 2 SD from physiological parameters. The study of the somatic function was performed using pharmacological tests. A four-day test for sensitivity to GH was performed to confirm the syndrome of biologically inactive GH. In 50 children with confirmed syndrome of biologically inactive GH, the presence of D112G mutation in gene of GH was determined by the method of polymerase chain reaction. Results. Characteristic hormonal disorders — low level of insulin-like growth factor‑1 (IFR‑1) against the background of normal level of GH were found in patients with syndrome of biologically inactive GH under the body mass index (BMI) not lower than 50 percentile for the given age and gender. The results of the study on the presence of substitution in the GH gene (C475 →T, Asp138→Gly) in patients with the syndrome of biologically inactive GH indicate that a definite substitution has not been detected in the whole group of the examined — the genotype of all genotypic patients C/C (Asp/Asp). Conclusions. Genetic study did not detect mutation of D112G in the GH gene of children in Ukraine, patients with syndrome of biologically inactive GH. The main criteria for diagnosing the syndrome of biologically inactive GH is normal or elevated level of GH, decreased IGF‑1, as a rule, positive response to sensitivity to GH, BMI more than 50 percentile for a specific age and gender, the absence of somatic pathology. For the final of genetic confirming the syndrome of biologically inactive GH, the gene sequencing will be informative for detecting  isorders of its structure in all sites.