Mutation Impact Visualizer
Select a genetic mutation to see how it changes protein structure, disrupts normal function, and causes disease. Compare normal and mutant proteins side by side.
Select a Mutation
Normal: HBB (Wild-type)
Mutant: HBB E6V
DNA Change
GAG → GTG
Protein Change
Glutamic acid → Valine at position 6
Chromosome
11p15.4
What Goes Wrong
Normal Function
Beta-globin forms part of hemoglobin, the oxygen-carrying protein in red blood cells. Normal hemoglobin (HbA) is soluble and allows red blood cells to remain flexible, squeezing through tiny capillaries to deliver oxygen throughout the body.
Mutant Effect
The E6V mutation replaces a charged, hydrophilic glutamic acid with a hydrophobic valine at position 6. This creates a sticky hydrophobic patch on the surface of hemoglobin S (HbS). When deoxygenated, HbS molecules polymerize into long, rigid fibers that distort red blood cells into a sickle shape.
Disease Mechanism
Sickled red blood cells are rigid and sticky. They block small blood vessels, causing excruciating pain crises, organ damage, stroke, and chronic anemia. The sickled cells also die prematurely (10–20 days vs 120 days normal), overwhelming the body’s ability to replace them.
Amino Acid Comparison
Glutamic acid
Glu (E)
Negatively charged, hydrophilic, polar
Valine
Val (V)
Nonpolar, hydrophobic, small
Why This Matters
A charged, water-loving amino acid is replaced by a greasy, water-avoiding one — creating a sticky patch that causes hemoglobin molecules to clump together.
How Gene Editing Could Fix It
Casgevy (CRISPR/Cas9) edits the BCL11A enhancer in patient’s stem cells to reactivate fetal hemoglobin (HbF), which doesn’t polymerize with HbS. FDA-approved December 2023 — the first CRISPR therapy ever approved. Base editing approaches are also in trials to directly correct the E6V mutation back to normal.
Disease Stats
Prevalence
~100,000 Americans affected; ~300,000 births/year worldwide. Most common in populations of African, Mediterranean, Middle Eastern, and Indian ancestry.
Inheritance Pattern
Autosomal recessive
Current Treatments
Hydroxyurea (increases fetal hemoglobin), blood transfusions, bone marrow transplant, Casgevy (CRISPR gene therapy), Lyfgenia (lentiviral gene therapy).
Educational Disclaimer
This tool is for educational purposes only. Protein structure visualizations are simplified representations and do not reflect actual 3D folding. Disease mechanisms are summarized for clarity. This is NOT medical advice. Always consult a qualified healthcare professional and certified genetic counselor for clinical interpretation of genetic variants.