IGF1 and Obesity: The distinctive features of LS include short stature (−4 to −10 SDS below median height), characteristic facial features, reduced head circumference, obesity, acromicria (i.e., smallness of the extremities), high basal serum GH, low to undetectable serum IGF1, and a lack of response to the administration of exogenous GH (Table 1) [10].