Defects of androgen receptor gen (Xc 11-12) leadre cellular insensitivity to these steroids. Androgen action is curently measured 'in vitro' in cultures of fioroblosts from genral skin, since expression of the androgen receptor occurs is these cells. This method has so been usaly available in Chile. This work was aimed to develop and aoply a method to study androgen binding and response properties in normal 46XY, hypospadics and androgen insensitive ndividuals. Cell cultures of our subjects showed the tipicol prooerties of fioroblasts, and their androcen binding ndicotors were similar to those previously reported. Mean dissociation constant was 4.02 ± 3.4 × 10-10 M. Mean rnexima binding capacity in normal controls (41.3 ± 23 frnol/mg prot.) was rot different from than of patients with hypospadia or androgen rsensitivity (39 3 ± 32 y 34.1 ± 20, respectively), but binding after androgen treatment for 24 h was significantly higher in controls than in both kincs of patients. Thus, this me
