Jolie has sickle-cell trait, a temporary, relatively mild form of sickle-cell anemia, but does not have full-blown sickle-cell anemia. Her condition is most likely the result of
◦ incomplete dominance between one allele for normal blood cells and one for sickle-shaped cells.
◦ two recessive alleles for sickle-shaped cells.
◦ a dominant sickle-shaped cell allele and a recessive normal blood cell allele.
◦ two dominant alleles for normal blood cells.