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P30 (PSA)

Definition

Prostate-specific antigen, a glycoprotein secreted by the male prostate gland and present in semen at high concentrations. ELISA or lateral-flow immunochromatographic tests for p30 are the standard confirmatory method for identifying a stain as semen in forensic laboratories worldwide.

Related terms

Acid Phosphatase (AP)
An enzyme present at high concentrations in seminal plasma. The Brentamine Fast Violet B (or SERI AP) spray test detects acid phosphatase...
Alpha-Amylase
Salivary enzyme. Detected by starch-iodine (clear zone in blue background) or the Phadebas reagent (blue colour from dye-linked starch). Concentration in saliva...
Barberio Test
Presumptive semen test. Saturated picric acid reacts with spermine to form yellow rhombic spermine picrate crystals.
Discriminating Power
The statistical ability of a typing system to distinguish one individual from another in a given population. Expressed as the probability that...
Florence Test
Presumptive semen test. Iodine plus potassium iodide reacts with choline in semen to form dark-brown rhombic / needle-shaped choline iodide crystals.
Hp, Gc, Tf
The classical serum-protein polymorphism panel: haptoglobin (binds free haemoglobin; Hp1-1, Hp2-1, Hp2-2 phenotypes), group-specific component (vitamin D binding protein, Gc1F / Gc1S...
Isoenzyme / Polymorphism
Different molecular forms of the same enzyme separable by electrophoresis. Forensic polymorphic markers have several common alleles in the population, so a...
PGM, EsD, AK, GLO
The classical RBC isoenzyme panel: phosphoglucomutase, esterase D, adenylate kinase, glyoxalase I. All polymorphic, all typed by starch-gel or isoelectric-focusing electrophoresis of...
Precipitin Test
A serological method in which an antiserum specific to one species' proteins is mixed with an extract of an unknown specimen. Formation...
Random Match Probability (RMP)
The probability that a randomly chosen unrelated person from the relevant population would match the evidence profile by chance. A very small...
Secretor
An individual whose ABO blood group antigens are expressed on red blood cells and also released into body fluids such as saliva,...
Secretor Status
A genetic trait that determines whether a person expresses their ABO blood group antigens in secreted body fluids such as saliva, semen,...

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