What is a heterozygous sickle cell?

Sickle cell disease is a disorder characterised by sickling of the red blood cells whilst under oxygen stress 1. Normal physiology : no change in shape occurs when under oxygen stress, in most of the red cells. 2. read more

Sickle cell trait describes a condition in which a person has one abnormal allele of the hemoglobin beta gene (is heterozygous), but does not display the severe symptoms of sickle-cell disease that occur in a person who has two copies of that allele (is homozygous). read more

A heterozygote advantage describes the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype. The specific case of heterozygote advantage due to a single locus is known as overdominance. read more