Guidance

Autosomal DNA relationship testing (FSR-GUI-0014)

Guidance for practitioners on autosomal STR relationship testing, replacing FSR‑G‑228. Principles also apply to other autosomal markers like In/Dels and SNPs.

• From: Forensic Science Regulator
• Published: 24 February 2026

Documents

Autosomal DNA relationship testing (accessible)

Ref: FSR-GUI-0014

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Autosomal DNA relationship testing

Ref: FSR-GUI-0014

PDF, 605 KB, 45 pages

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Details

This document provides guidance and recommendations to practitioners providing relationship testing services using autosomal DNA short tandem repeat profiling. This document applies only to short tandem repeat (STR) markers, although the ethos of the guidelines can be applied to other classes of autosomal markers such as In/Dels and single nucleotide polymorphisms (SNPs).

This document replaces the previously published FSR-G-228: DNA relationship testing using autosomal short tandem repeats, which you can access at the National Archives.

Published 24 February 2026