Background: fl/d3 polymorphism in human GH receptor was correlated with the response to GH therapy in different groups of children with short stature.
Aim: This is a 2-yr retrospective study which evaluates the influence of fl/d3 polymorphism to the 1st-and 2nd-year response to GH replacement therapy in Greek children with isolated GH deficiency (GHD).
Subjects and methods: A total number of 195 pre-pubertal Greek children were studied (121 controls and 74 patients with GH peak <10 ng/ml). Patients with deficiency were treated with exogenous GH at a mean dose of 28.8 μg/kg.d. Multiplex PCR was used to genotype all children for fl/d3 polymorphism, followed by statistical analysis. The main parameters which were used to assess the association of genotype with the response to GH replacement were height SD score (SDS), height gain SDS, and growth velocity (GV) expressed as cm/yr and SDS.
Results: Our results revealed that the frequency of d3-homozygosity in the Greek population was 8.26%. No association was detected between the presence or abcense of GHD and genotype. Moreover, no connection between genotype and sex was observed. First-year height SDS, height gain SDS, and GV SDS were significantly higher in d3-carriers (p<0.05). However, this difference did not appear in the 2nd year of treatment.
Conclusions: In our study, the d3-polymorphism seems to be associated with a higher efficacy to GH replacement, at least at the beginning of the treatment.