Q. A 35-year-old man comes to the clinic for a follow-up examination. On clinical examination, there is mild splenomegaly with pale conjunctiva. Further investigations show hemoglobin levels of ( 11 mg/dl), high MCHC with low MCV. The physician suspects a genetic disease, so cytogenetic tests are ordered. A mutation in the proteinous part of hemoglobin is found, this mutation causes the substitution of glutamic acid with lysine. What is the most likely diagnosis?