Hemophilia is a condition in which blood does not clot naturally, and a person with hemophilia could bleed to death if injured. a hemophiliac must receive regular injections of what blood part to stay alive?

Depends on the type of hemophilia they have: people with hemophilia A are deficient in factor VIII (a clotting protein) and use infusions of factor VIII concentrate to control bleeds. People with hemophilia B are deficient in factor IX and use infusions of factor IX concentrate to control bleeds.

Amutation is basically the change in the gene, caused by alteration of single based units in the dna, or the genes or chromosomes were rearranged in the dna