The ABO system consists of A, B, AB, and O blood types. People with type A have antibodies in the blood against type B. People with type B have antibodies in the blood against type A. People with AB have no anti-A or anti-B antibodies.
Developmental dyslexia, or specific reading disability, is a disorder in which children with normal intelligence and sensory abilities show learning deficits for reading.
The primary cause, however, remains unidentified. Developmental. dyslexia affects between 5% and 17% of the. population, representing a very large number of. children. Although dyslexia is biological, reading. can be improved with specific kinds of instruction.