Endocrine Abstracts

Objectives: There is some evidence that growth hormone deficient (GHD) children with a common polymorphism of the growth hormone receptor (GHR) gene, resulting in deletion of exon-3 (d3GHR) on one (d3/fl) or both alleles (d3/d3), have a better growth response to rhGH than those who express exon 3 on both alleles (fl/fl). We speculated that adult patients with this polymorphism may also be more sensitive to rhGH and less likely to be symptomatic from GHD than those without. To investigate this hypothesis we studied the relationship between serum IGF-1, body composition and QoL scores in GHD adults treated with rhGH and their expression of exon 3 of the GHR gene.

Patients and measurements: One thirty one (54% male) adult patients with GHD were studied. All patients had been treated with rhGH for impaired QoL for at least 1 year. Expression of exon-3 on the GHR gene was determined in DNA isolated from peripheral blood. QoL was measured using the AGHDA scale, 2 other validated QoL instruments and the Visual Analogue Scale (VAS) for energy levels. Body composition was measured using a bioimpedance meter to determine percentage fat mass. Serum GH and IGF-1 levels were measured by chemiluminescent immunometric assays.

Results: There frequency of the different genotypes in the population was 55% fl/fl, 39% d3/fl and 6% d3/d3. There was no difference in the QoL, body composition and serum IGF-1 levels in patients with the fl/fl genotype compared to those with the d3/d3 or d3/fl genotype.

Conclusion: Expression of exon-3 of the GHR gene does not influence serum IGF-1, QoL or body composition of GHD adults on rhGH for more than 1 year.