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HbS

Hemoglobin electrophoresis Biomarker

Sample Needed

Collection Type: Blood

Body System

Related System: Hemoglobin electrophoresis

Overview

Hemoglobin S (HbS) is an abnormal variant of the β‑globin chain caused by a single amino‑acid substitution; it polymerizes under low-oxygen conditions, deforming red cells into the characteristic “sickle” shape. The HbS measurement (usually reported as percent of total hemoglobin on hemoglobin electrophoresis or HPLC) identifies carriers (sickle cell trait) and people with sickle cell disease (homozygous or compound heterozygous states). Testing is indicated for unexplained anemia, recurrent pain crises, jaundice, delayed growth, or for newborn screening and prenatal/family counseling. Prevalence varies by ancestry (higher in people of African, Mediterranean, Middle Eastern, and Indian descent). Newborns have high fetal hemoglobin (HbF) that alters interpretation; recent transfusion also changes percentages. Gender has no direct effect; age and transfusion status do.

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Test Preparation

No special preparation is required

Why Do I Need This Test

Profile: part of Hemoglobin electrophoresis / HPLC panel (hemoglobinopathy screen).
Symptoms: unexplained anemia, painful vaso‑occlusive episodes, chronic fatigue, jaundice, recurrent infections, splenic dysfunction.
Diagnoses: sickle cell trait (AS), sickle cell disease (SS, SC, S/β‑thalassemia) and other HbS-containing genotypes.
Abnormal reasons: inherited HbS allele, compound hemoglobinopathies, recent transfusion (lowers %), or neonatal HbF interference.
Biological meaning: presence indicates one or more β‑globin gene mutations producing sickle hemoglobin.
Lifestyle: dehydration, extreme exercise, high altitude exacerbate symptoms but do not create HbS.
Family history: relatives with sickle cell disease/trait or ancestry from high-prevalence regions prompts testing.

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Symptom Checker

Understanding Test Results

0% HbS: Normal no sickle hemoglobin detected.
~30–45% HbS in an adult (with remaining predominantly HbA): consistent with sickle cell trait (heterozygous AS); usually asymptomatic but at risk for rare complications under severe stress.
>80–95% HbS with absent HbA (and variable elevated HbF): typical of sickle cell disease (homozygous SS); associated with chronic hemolytic anemia, vaso‑occlusive crises, infection risk, organ damage.
Approximately equal proportions of HbS and HbC (~40–55% each) indicate HbSC disease.
Intermediate or variable HbS percentages (50–90%) may reflect compound states (S/β‑thalassemia) or recent transfusion (which can markedly lower measured HbS); newborn results are affected by high HbF and require follow-up testing after ~6 months.
Abnormal HbS levels warrant genetic counseling and confirmatory testing if clinical management is needed.

Normal Range

0% (absent)

FAQs

Q: What is HbS slang for?

A: HbS is slang for hemoglobin S, an abnormal form of the beta‑globin protein caused by a mutation (glutamic acid valine at position 6). It makes red blood cells sickle under low oxygen, producing sickle cell trait with one HbS gene or sickle cell disease with two. Carriers may be asymptomatic or have complications and often benefit from genetic counseling.

Q: What is HbS medical?

A: HbS (hemoglobin S) is an abnormal hemoglobin variant caused by a β‑globin gene mutation. When deoxygenated it polymerizes, sickling red cells and causing hemolytic anemia, vaso‑occlusion, pain crises, and organ damage. It’s inherited in an autosomal recessive pattern (sickle cell trait or disease). Diagnosis uses hemoglobin electrophoresis/newborn screening; treatment includes hydration, pain control, hydroxyurea, transfusions, and stem‑cell transplant.

Q: What is HbS in full?

A: HbS stands for hemoglobin S (sickle hemoglobin). It is an abnormal beta‑globin variant caused by a point mutation (glutamic acid to valine at position 6). HbS polymerizes when deoxygenated, causing red cells to sickle, which leads to hemolytic anemia, vaso‑occlusion and pain crises. Homozygotes have sickle cell disease; heterozygotes have sickle cell trait.

Q: What is HbS biology?

A: HbS is an abnormal haemoglobin caused by a single point mutation in the β‑globin gene (glutamic acid valine at position 6). Deoxygenated HbS polymerizes into rigid fibers that deform red cells into sickle shapes, promoting hemolysis, reduced cell lifespan, and vaso‑occlusion. Homozygous individuals develop sickle cell disease; heterozygotes (trait) are often asymptomatic but can have complications under extreme stress or hypoxia.

Q: What's HB in chat?

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Q: What is the HbS test used for?

A: The HbS test detects hemoglobin S, the abnormal hemoglobin variant responsible for sickle cell trait and sickle cell disease. It is often performed as part of a hemoglobin electrophoresis panel or newborn screening. The test helps confirm carrier status, diagnose sickle cell disease, and guide family planning or treatment decisions such as hydroxyurea therapy, transfusions, or genetic counseling.