Laron Syndrome 5 cases. Clinical and molecular evaluation

İntraduction: Laron Syndrome is defined as growth hormone deficiency or insensitivity. Our aim is to discuss the clinical,laboratory findings and growth hormone receptor gene mutation analysis of the Laron Syndrome cases.Cases: 5 patients’(two girls, 3 boys) pretreatment height SDS, annual growth rate, growth hormone, IGF-1,IGFBP3, initial treatment age were recorded. The height SDS,annual growth rates, the doses of the drugs were evaluated to find the treatment responce. Growth hormone receptor gene mutations were evaluated. The mean age was 3.0±2.7 years, height SDS was -5.06±0.7 and target height SDS was -0.72±0.95. Pretreatment annual growth rate was 3.5±1.7cm(1.8-6.0). Basal growth hormone levels were over 40 pg/ml in all patients. Mean basal value IGF was 9.7±9.9ng/ml. Mean IGF jeneration test’s IGF value was 10.7±9.8ng/ml. Due to the difficulties to get the recombinant IGF treatment; we could started the therapy at the mean age of 4.06±2.6 years. Usually the doses of the drugs per year were under the expected doses for the patients. The average annual growth rates were 3.73 cm/year, 4,24 cm/year, 3,55 cm/year; 1st, second and third year respectivelly. Growth hormone receptor gene analysis revealed; homozygote missense c.1630 A>C(p.I544L) mutation in one patient and; c.1419 C>T(p.S473S) polimorfism in two siblings and c.1681 C>A(p.P561T) homozigot mutation in one patient, c.629 T>G(p.V210G) ve c.1567 A>C(p.I526L) compound heterozigot mutation in one patient. As a result, in the Laron syndrome patients had been shown that an adequate clinic respons to recombinant IGF treatment.