An athlete who normally has plenty of endurance is admitted to the emergency room with symptoms of sickle cell anemia, which include pain crisis in multiple limbs from lack of oxygen as a result of a track competition at high altitude. Suspecting sickle cell trait, doctors decide to screen the athlete's beta-globin gene for sickle-cell mutations. What is the general genetic term that would best describe the athlete's beta-globin genotype of the alleles being tested?
HETEROZYGOUS