Hp, Gc, Tf
Definition
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 / Gc2 alleles) and transferrin (iron-carrier, TfC / TfB / TfD variants).
- Panel
- Haptoglobin, group-specific component, transferrin
- Hp phenotypes
- Hp1-1, Hp2-1, Hp2-2
- Gc alleles
- Gc1F, Gc1S, Gc2
- Tf variants
- TfC, TfB, TfD
Common questions
Why has this serum-protein panel largely fallen out of forensic casework use?+
STR DNA typing offers far greater discriminating power from smaller and more degraded samples than protein polymorphism phenotyping ever could, so Hp, Gc and Tf typing is now mainly of historical or teaching interest rather than an active casework technique.
What kind of sample was this panel originally applied to?+
It was applied to bloodstains and other biological fluids where the relevant serum proteins survived, using electrophoretic or immunological typing methods that predate DNA profiling in forensic serology.
Could this panel still play any role today?+
It occasionally has value in historical case review or in contexts studying protein stability and degradation, but for identification and comparison purposes it has been superseded by DNA-based methods.
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