Somatomedin C (insulin-like growth factor 1) in adults with Down's syndrome

In a Norwegian institution for the mentally retarded, 29 adults with chromosomally verified Down's syndrome were compared to other mentally retarded patients with respect to serum somatomedin C (SmC) (insulin-like growth factor 1 [IGF-1]). Contrary to what has been observed in children, no shortage of SmC could be demonstrated in the adults with Down's syndrome. The results were within the normal range, and there was no difference between those with Down's syndrome and the other mentally retarded patients. Human growth hormone (HGH) and body height were studied in a previous work. Some correlations with these data are, nevertheless, included herein because they are of relevance. SmC correlated with body height in Down's syndrome, while there was no correlation between SmC and HGH or between HGH and body height.