The co-inheritance of Hb C or β- thalassemia (β-thal) genes with the sickle cell gene affects the phenotypic expression of this combination. A complex network of gene modifiers seems to affect the phenotypic expression of the sickle cell complications.
Does sickle cell change phenotype?
Although it is a single gene mutation, it has multiple phenotypic expressions that constitute the complications of sickle cell disease. The frequency and severity of these complications vary considerably both latitudinally in patients and longitudinally in the same patient over time.
What is the phenotype of sickle cell trait?
Any combination of two of these alleles represents an individual’s genotype. Individuals with genotype AS have the sickle cell trait phenotype, and individuals with SS genotype have the sickle cell disease phenotype.
What is the phenotype of homozygous individuals affected with sickle cell?
In most situations, individuals who are heterozygous for sickle-cell anemia are phenotypically normal. Under these circumstances, sickle-cell disease is a recessive trait. Individuals who are homozygous for the sickle-cell allele (ss), however, may have sickling crises that require hospitalization.
What blood type carries sickle cell?
It is an inherited condition in which both hemoglobin A and S are produced in the red blood cells, always more A than S. Individuals with sickle cell trait are generally healthy.
Do both parents need to have the sickle cell trait?
You inherit 1 set from your mother and 1 set from your father. To be born with sickle cell disease, a child has to inherit a copy of the sickle cell gene from both their parents. This usually happens when both parents are “carriers” of the sickle cell gene, also known as having the sickle cell trait.
Is Sickle Cell Anemia a point mutation?
As mentioned, sickle-cell anemia is the result of a change in a single nucleotide, and it represents just one class of mutations called point mutations. Changes in the DNA sequence can also occur at the level of the chromosome, in which large segments of chromosomes are altered.
Is Sickle Cell Anemia A missense mutation?
Missense mutation: A genetic change that results in the substitution of one amino acid in protein for another. A missense mutation is responsible for sickle hemoglobin, the molecular basis of sickle cell trait and sickle cell anemia.