A new forensic science standard in the United States establishes requirements for laboratories conducting familial DNA searches, with an emphasis on scientific validation, documented procedures and the protection of genetic privacy.
The Academy Standards Board (ASB), operating under the American Academy of Forensic Sciences, announced the publication of ANSI/ASB Standard 199, Standard for Familial DNA Searching, First Edition, 2026, on November 13.
Familial DNA searching is an investigative technique that examines forensic DNA databases for individuals who may be close biological relatives of an unknown person associated with a crime-scene DNA profile.
Unlike a conventional database search seeking a direct profile match, a familial search deliberately evaluates genetic similarities that could indicate a parent-child or sibling relationship.
Such searches can generate investigative leads when a direct DNA match is unavailable.
However, a potential familial association does not establish the identity of the unknown DNA contributor or prove involvement in a crime.
The newly published standard establishes requirements for laboratories performing these searches.
It requires documented policies addressing the acceptance of search requests, administrative responsibilities, the search process and the reporting of results.
The standard also addresses the protection of individual privacy and the confidentiality of familial search findings.
These safeguards are particularly important because familial searching can involve individuals whose own DNA profiles are not present in a forensic database.
A database profile belonging to a relative may generate an investigative lead concerning another person who has never provided a forensic DNA sample.
The standard further establishes validation requirements and addresses training for personnel evaluating familial search results.
Validation is necessary to establish whether a laboratory's methods perform adequately for their intended purpose.
Familial search procedures can involve statistical comparisons and candidate rankings, making appropriate interpretation essential.
The results depend on the quality of the DNA profiles, the relationships being investigated, the analytical methods and the assumptions used in the statistical evaluation.
Importantly, the ASB distinguishes familial DNA searching from forensic investigative genetic genealogy.
Familial DNA searching generally involves deliberate searches of forensic DNA databases for possible close relatives.
Investigative genetic genealogy may use different genetic markers, genealogical databases and family-history research to investigate more distant biological relationships.
The new standard explicitly excludes forensic investigative genetic genealogy from its scope.
It also does not apply to partial matches encountered incidentally during routine forensic database searches.
The publication provides a framework for laboratories that perform familial DNA searches, but it does not automatically authorize the technique in every jurisdiction.
The legal and operational use of familial searching remains subject to applicable laws, policies and database restrictions.
The standard's publication also does not mean that every forensic laboratory is required to implement familial DNA searching.
For forensic practitioners, the development highlights the importance of transparent procedures, scientifically validated methods and appropriate safeguards when genetic information is used to generate investigative leads.