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.
Dyslexia is the most common learning disability. It is defined by the International Dyslexia Association as: a specific learning disability that is neurological in origin. Dyslexia is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities.