Genetic causes of mental retardation

Mental retardation (MR) is defined as congenital or early onset lifelong impairment of cognitive and adaptive functioning (IQ < 70). It affects about 3% of the Western population. The causes are heterogeneous. Numerical or structural chromosome abnormalities are responsible for 10–20% of the mild cases (MMR) and 40% of the severe cases (SMR). Among them… CONTINUE READING