a: Anemia defined according to WHO, b: Leucopenia defined as total leucocyte count less than 3000/mm3, c: Lymphopenia defined as absolute lymphocyte count less than 1000/mm3, d: Thrombocytopenia defined as a total platelet count less than 1,00,000/mm3, e: Low C3/ Low C4/ Both. This evidence concerns the gene C4A and lymphopenia.