A stain recovered from bedclothes gives a positive acid phosphatase reaction. To definitively establish that the stain is human semen before DNA profiling, the laboratory should perform which confirmatory test?

• A Florence test for choline crystals
• B Immunological assay for prostate specific antigen (p30) ✓
• C Barberio test for spermine
• D Amylase estimation in the stain extract

Explanation

Acid phosphatase activity is only a presumptive screening test for semen and can be positive with vaginal secretions and other body fluids. Detection of prostate specific antigen (p30 protein) by immunodiffusion or ELISA confirms the presence of human seminal fluid even in azoospermic or vasectomised men. The Florence and Barberio tests are older presumptive crystal tests, and amylase indicates saliva, not semen.

Reference: Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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