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Index

The whole register

Thirty-one entries in six sections. Every one of them is a single technique, register, instrument or body, with what it can and cannot carry.

The Method

How a profile is actually produced.
No.	Entry	What it covers
1.01	The Southern blot	The original approach transferred separated fragments to a membrane and probed them, and it needed a large, fresh sample and days of work.
1.02	Multilocus probes	The first probes read many sites at once and produced a barcode-like pattern that was powerful for identity and very hard to interpret in a mixture.
1.03	PCR and the single locus	Amplification changed the requirement completely: enough copies could be made from a very small starting amount to read one site at a time reliably.
1.04	STR multiplexes	Short repeated sequences at many sites, amplified together in one reaction, are what every modern profile and every national database is built on.
1.05	Capillary electrophoresis	Fragments are separated by size in a thin capillary and detected by fluorescence as they pass a window.
1.06	What a profile is	A profile is a list of numbers at named sites — not a picture, not a sequence, and not a person.

The Limits

What the technique cannot carry.
No.	Entry	What it covers
2.01	Transfer	DNA moves — hand to bench, bench to garment, glove to item — so presence establishes contact with the material, not participation in an event.
2.02	Mixtures	When the peaks stop belonging to one person, interpretation becomes a statistical argument rather than a reading.
2.03	Low-template DNA	Pushing sensitivity produces drop-out, drop-in and stutter, and the result becomes partly a property of the method.
2.04	Probabilistic genotyping	Software models the ways a mixture could have arisen and reports a likelihood ratio, which moves the argument to the model.
2.05	Contamination	Documented laboratory failures are part of the technique's history and are why controls and elimination databases exist.
2.06	Contextual bias	Giving examiners the same mixture and different background information changes the conclusions they reach.

The Record

The documented history, including the exonerations.
No.	Entry	What it covers
3.01	Leicester, 1984	Alec Jeffreys noticed repeating sequences that varied enough between people to identify them, and called the result a genetic fingerprint.
3.02	The first exoneration	The technique's first use in a criminal investigation cleared a man who had already confessed, which is the reason it was trusted afterwards.
3.03	The Innocence Project	Post-conviction testing has overturned a documented and countable number of convictions.
3.04	Cleared of the method	Several early techniques were later withdrawn or restricted after review, which is how a forensic discipline is supposed to work.
3.05	The 2016 review	A national review examined which forensic methods had been validated and which had not.

The Registers

The databases, and the rules about them.
No.	Entry	What it covers
4.01	National DNA Database	A retained collection of profiles, and a continuous argument about who should be on it and for how long.
4.02	CODIS	The American index is a set of core sites plus rules about what may be searched against what.
4.03	The Interpol Gateway	Cross-border comparison needs agreement on which sites everybody reads.
4.04	S. and Marper	A European court judgment in 2008 held that indefinite retention of profiles from people not convicted was disproportionate, and the law changed.
4.05	Familial searching	Searching for a partial match to find a relative rather than the person turns a register into something wider than it was authorised to be.
4.06	Genetic genealogy	Comparing a crime-scene profile against public genealogy data reaches people who never consented to be reachable.

The Instruments

The machines themselves.
No.	Entry	What it covers
5.01	The autoradiograph	The early output was a film, read by eye, and its bands are the image everyone still pictures.
5.02	The thermal cycler	A block that heats and cools on a schedule is the machine that made everything after it possible.
5.03	The capillary array	A bundle of fine tubes and a detector window, replacing a slab of gel.
5.04	Rapid DNA boxes	Self-contained units that produce a profile without a laboratory, and the argument about where they should be allowed.

Standards

Who decides what counts as correct.
No.	Entry	What it covers
6.01	NIST core loci	Somebody has to decide which sites everyone reads, and publish the reference data behind them.
6.02	SWGDAM	Interpretation guidelines that laboratories work to, revised as methods change.
6.03	ENFSI	The European network that runs collaborative exercises so laboratories can be compared with each other.
6.04	The Forensic Science Regulator	A statutory code setting quality requirements, and the power to say a laboratory is not meeting them.