7. Data reported from various clinics in the country show that in 60% of the cases identified as mentally retarded, causes can be attributed to
generic disorders. Consanguinous marriages i.e. marriage between uncle-niece, nephew-aunt, first cousins or related cousins have greater
chances of producing a child with generic disorders including mental retardation. In case there is already a child with mental retardation, the parents should seek genetic counselling before planning to have another child.