Laron syndrome: typical and atypical forms.

Since the original description of LS by Laron in 1966, this rare condition has continued to assume an importance far beyond the number of affected cases as a unique model of GHR dysfunction. Recently, the potential of therapy with recombinant IGF-I has led to the recruitment and detailed study of patients from a heterogeneous genetic and geographical background and the realization that hereditary GH resistance is itself a heterogeneous condition, with considerable variation in clinical, biochemical and molecular features between patients. For the scientist, further study of the 'atypical' LS patient may lead to important insights into the signalling pathway between GH and IGF-I. For the clinician, the challenge lies in establishing the contribution of inherited forms of GH resistance to the group of children with idiopathic short stature, with the potential of offering therapy to these patients based on an understanding of the aetiological basis of their disorder.