This project first objective is to evaluate the safety and tolerability of the EGCG molecule (extracted form green tea) on children from 6 to 12 years old with Intellectual Development Disorder (Down syndrome and Fragile X syndrome).~The secondary objective is to evaluate the benefits of the EGCG on attention, memory, executive functions, language and adaptive behaviour of these children. Dyrk1A and homocysteine in plasma will also be quantified, using them as biomarkers of efficacy.
To evaluate safety and tolerability of epigallocatechin gallate (EGCG) in children from 6 to 12 years old with Intellectual Developmental Disorders (IDD) (Down syndrome or Fragile X syndrome).