{"id":"hemoglobin-s","name":"Hemoglobin S (HbS)","shortName":"HbS","aliases":["Hemoglobin S","HbS","Hgb S","Hb S","Sickle Hemoglobin","Hemoglobin S Quant","Hemoglobin S (HPLC)","Hemoglobin S %","Hb S, Quantitative","Hgb S %","HbS %","Sickle Hgb","Hemoglobin S Evaluation","Hemoglobin S, Quantitative"],"abbreviations":["HbS","Hb S","HGB S","Hgb S"],"loinc":[{"code":"4625-0","primary":true},{"code":"44923-1","primary":false},{"code":"32683-5","primary":false},{"code":"4621-9","primary":false}],"specimen":"whole-blood","units":[{"ucum":"%","display":"%"}],"referenceRanges":[{"population":"Adults","low":null,"high":0,"unit":"%","unitDisplay":"%","note":"Healthy people have no HbS. ARUP prints 0.0 for hemoglobin S and a negative result for its sickle test, Mayo lists 0.0 for hemoglobin variants, and the University of Iowa prints 0%. The range is entered as an upper limit of zero, so any amount of HbS falls outside it. A result above zero does not by itself tell sickle cell trait from sickle cell disease, so read the full hemoglobin report. For context, NHLBI describes about 40% HbS in sickle cell trait, and the NHS England handbook treats a variant share of 30% to 40% as typical for a carrier.","sources":[{"title":"Hemoglobin Evaluation by HPLC With Reflex to Electrophoresis and/or RBC Solubility (test 3017101)","url":"https://ltd.aruplab.com/Tests/Pub/3017101","publisher":"ARUP Laboratories"},{"title":"Hemoglobin S Evaluation with Reflex to RBC Solubility (test 3016616)","url":"https://ltd.aruplab.com/Tests/Pub/3016616","publisher":"ARUP Laboratories"},{"title":"Hemoglobin Variant, A2 and F Quantitation, Blood (test HGBCE)","url":"https://www.testcatalog.org/show/HGBCE","publisher":"Mayo Clinic Laboratories"},{"title":"Hemoglobin Evaluation, Quantitation with Interpretation (Pathology Handbook)","url":"https://www.healthcare.uiowa.edu/path_handbook/handbook/test969.html","publisher":"University of Iowa Hospitals & Clinics"},{"title":"Sickle Cell Disease: Causes and Risk Factors","url":"https://www.nhlbi.nih.gov/health/sickle-cell-disease/causes","publisher":"National Heart, Lung, and Blood Institute (NIH)","year":2025},{"title":"Sickle cell and thalassaemia screening: laboratory handbook, Interpretation and reporting of antenatal screening results","url":"https://www.gov.uk/government/publications/sct-screening-handbook-for-antenatal-laboratories/interpretation-and-reporting-of-antenatal-screening-results","publisher":"NHS England (NHS Sickle Cell and Thalassaemia Screening Programme)"}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"How much of your hemoglobin is the sickle type, HbS. Most people have none. A result above zero needs the full hemoglobin report to interpret.","url":"https://bloodtesttracker.com/markers/hemoglobin-s","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}