Tests
An allergy blood test measures the amount of allergy-causing antibodies called immunoglobulin E (IgE). Antibodies are proteins that your immune system makes to fight foreign substances, such as viruses and bacteria . But your immune system may also make them in response to allergens. These are harmless substances, such as pollen and peanuts, that may cause an allergic reaction in some people.
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Tests
An AFP tumor marker test is a blood test that measures the level of AFP (alpha-fetoprotein) in a sample of your blood. AFP is a protein that the liver makes when its cells are growing and dividing to make new cells. AFP levels are normally high in a fetus, but after birth, they drop very low. Healthy children and adults who aren’t pregnant have very little AFP in their blood.
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Tests
Alpha-1 antitrypsin (AAT) testing uses a sample of blood or a cheek swab to diagnose a condition called alpha-1 antitrypsin deficiency (AAT deficiency). This condition is sometimes known as "alpha-." or AATD. If you have AAT deficiency, your body doesn't make enough AAT.
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Indicators
Alpha-1-acid glycoprotein 1 (201 aa, ~24 kDa) is encoded by the human ORM1 gene. This protein may play a role in immunosuppression and small molecule transport.
Indicators
Alpha-2-macroglobulin (1474 aa, ~163 kDa) is encoded by the human A2M gene. This protein has activity as a protease inhibitor.
Indicators
Alpha-fetoprotein (609 aa, ~69 kDa) is encoded by the human AFP gene. This protein plays a role in the binding to copper, nickel, bilirubin and fatty acids in the fetal circulation.
Tests
An AFP test is a blood test that measures the level of alpha-fetoprotein (AFP) in your blood when you are pregnant. The test checks your baby's risk of having certain birth defects and genetic problems , but it does not diagnose any health conditions. The test is usually done between 15 and 20 weeks of pregnancy .
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Tests
An ALT test measures the amount of ALT in your blood. This test is commonly used to help diagnose liver damage or disease .
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Glossary Term
Alternate Splicing is a process in which multiple protein isoforms or products are generated from a single gene as a result of splicing together different nonconsecutive exons during the processing of initially identical nascent transcripts of a gene into mature mRNA transcripts. An exon may be connected to any one of several alternative exons to form the mRNA and generate related proteins, often in a tissue or developmental stage specific manner.
Pcr Terms
Article
Research record from Anal Chem, 2026-08-01. PMID 42610923.
Tests
An ammonia levels test measures the amount of ammonia in a sample of your blood. Ammonia is also called NH3. It is a normal waste product in your body. Healthy bacteria in your intestines make ammonia when you digest protein in the foods you eat.
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Tests
An amylase test measures the amount of amylase in your blood or urine (pee). Amylase is an enzyme, a protein that speeds up chemical reactions in your body. Amylase helps you digest carbohydrates . Most of the amylase in your body is made by your pancreas and salivary (spit) glands.
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