National DNA Database UK: How DNA Records Work in England and Wales

The National DNA Database (NDNAD) is the main police DNA database used across the UK to compare DNA profile records from individuals and crime scenes. In practice, it helps investigators connect a person to forensic material, link separate crime scenes, and generate investigative leads that might otherwise be missed. The system remains operationally important: official figures published in 2025 reported a DNA match rate of 65.7% when a crime scene profile was loaded and searched on the database. For current official figures, the Home Office publishes National DNA Database statistics.

The database is centrally managed through the Forensic Information Databases Service (FINDS) within the Home Office on behalf of policing. It is not designed as a public-facing register, and its use is tightly framed by criminal procedure, data protection rules, and oversight mechanisms intended to balance investigative value with privacy rights.

What does the National DNA Database actually store?

A common misunderstanding is that the police database keeps a person’s entire genetic code. In England and Wales, the key record retained on the NDNAD is a DNA profile, not a full genome sequence. Official guidance describes NDNAD records as DNA profiles derived from samples taken from crime scenes or from people arrested for recordable offences, together with associated data needed for lawful searching, matching and record integrity.

In routine searching, a full match is based on the numerical DNA profile used by the UK system, rather than on storing someone’s full biological blueprint.

In practical terms, the information linked to a record can include:

• whether the profile comes from a person or a crime scene

• the fact that the sample was taken in connection with a police investigation

• associated administrative and case data needed to evaluate a match and manage the record lawfully

• profile information used for automated comparison on the database

This distinction matters. A DNA sample may contain far more biological information, which is one reason retention rules for samples are stricter than for profiles. If you want a non-police explanation of what a profile is, our page on the DNA genetic profile gives a simpler overview of how a genetic profile is used for identity comparison rather than ancestry or health analysis.

Who can access the data?

Access is restricted. Home Office material explains that the NDNAD is run centrally and that police forces are informed of matches but do not directly access the database itself. This is an important safeguard: it limits unnecessary handling of sensitive biometric data and keeps the system under a narrower governance framework.

That said, the existence of safeguards does not eliminate controversy. DNA databases continue to raise questions about privacy, proportionality, and the retention of biometric material from people who were arrested but not convicted. The UK framework explicitly tries to address that tension through statutory retention rules, Commissioner oversight, and deletion mechanisms.

When can police take a DNA sample in England and Wales?

If you are arrested, the police can usually take fingerprints and a DNA sample, such as a mouth swab or a head hair root, without your permission. However, that power is tied to the legal framework for policing and does not apply in the same way outside criminal procedure. The police also cannot take or retain DNA under this framework for a non-recordable offence.

This is precisely why criminal justice DNA use must not be confused with consumer or private testing. A police database profile is part of a statutory forensic system, whereas a family or civil DNA test follows a completely different legal logic. For a clearer distinction, see our guide to the legal DNA test, which explains when DNA evidence can have formal legal weight outside the criminal database context.

How long can DNA records stay on the database?

Retention depends heavily on the person’s legal situation.

If someone is arrested and not charged, and has no previous convictions, their fingerprints and DNA profile will in most cases be deleted from the national databases. That is the general rule, although the police can apply in certain qualifying cases to keep the material for a limited period.

Where the case involves a qualifying offence and the statutory conditions are met, the police may seek permission to retain the DNA profile for 3 years. The legislation also allows an application to a District Judge for an extension of up to 2 further years.

Where there is a conviction, retention can be much longer and may be indefinite in many cases, although the law contains exceptions, especially for some first minor offences committed under the age of 18. Also, the DNA sample itself is usually destroyed once a profile has been obtained, and the statutory regime requires destruction of samples within defined limits unless further retention is lawfully authorised.

How can you find out whether your DNA is likely to be held?

There is no public search tool that lets you directly browse the NDNAD yourself. In practice, the first official route is the GOV.UK biometric data records service, which helps you determine whether your biometric data is likely to be on a police database. For broader police-record access, ACRO also states that individuals can make a Subject Access Request for personal data held on the Police National Computer.

In other words, if you were arrested or involved in a criminal investigation and want to understand your position, you usually start with the official biometric data route and then assess whether a broader access request or legal advice is necessary. That is more accurate in the UK context than assuming there is a single public file you can simply inspect.

Can you ask for deletion of your DNA data?

Yes, in some situations. In England and Wales, deletion is not handled the same way in every case.

First, some material should be deleted automatically under the statutory retention rules, especially where a person is not charged and no basis exists for extended retention. Second, there is also a Record Deletion Process for early deletion of certain records from the NDNAD, the national fingerprint database and the PNC.

If the police apply to keep your DNA profile after an arrest for a qualifying offence, you must be notified, and you have the right to make written representations to the Biometrics and Surveillance Camera Commissioner. The guidance states that you normally have 28 days to respond, and that a solicitor or representative may act on your behalf.

In practice, a deletion request may be especially relevant where:

• you were arrested but not charged

• the record should have been removed under the normal rules

• the retention appears disproportionate or factually incorrect

• you want an early deletion review under the national process

  
  

This issue also overlaps with consent and lawful purpose outside policing. That is why the limits discussed in our article on private detective and DNA test are relevant: police powers and private investigative conduct do not operate under the same legal permissions.

Final thoughts

The National DNA Database UK is a powerful forensic tool, but it is not a simple warehouse of everyone’s genetic information. In England and Wales, the system is built around DNA profiles, restricted access, retention rules, and oversight designed to limit misuse while preserving investigative value. That framework is still debated, particularly where innocent or uncharged people are concerned, but the legal position is more nuanced than the idea of a permanently stored full DNA record.

If your concern is personal rather than criminal, the right approach is usually to distinguish very clearly between police biometrics, court-usable legal DNA testing, and private information-only testing. Confusing those categories is one of the main reasons people misunderstand what a police DNA database can and cannot do.