UTC Most individuals with Down syndrome have mental retardation in the mild IQ 50 70 to moderate IQ 35 50 range 3 with individuals having Mosaic Down syndrome typically 10 30 points higher I think that IQ 70 85 is considered mild retardation while IQ 50 70 is considered moderate and less than IQ 50 is regarded as profound This should be checked and if appropriate amended 00 05 17 July 2009