nonrelated

Nonrelated is an adjective used to describe individuals or entities that do not share a meaningful familial or genealogical relation. The term appears across disciplines such as genetics, epidemiology, social research, and data analysis to indicate a lack of close kinship and to distinguish between relatives and those without known family connections.

In genetics and research design, nonrelated subjects are often preferred because shared ancestry can confound results. Studies that compare disease risk or test genetic associations aim to include nonrelated individuals to reduce bias from familial clustering. The definition of nonrelatedness can be operationalized using kinship coefficients or measurements of identity by descent to quantify how closely two people are related, and researchers may apply thresholds to designate unrelated pairs for analysis.

Beyond study design, the concept applies to data collections and privacy. Datasets that specify nonrelated individuals imply no immediate genetic or genealogical connections among participants, aiding statistical independence. In practice, distant relatives may exist in supposedly nonrelated samples; this phenomenon, known as cryptic relatedness, is something analysts attempt to detect and adjust for.

Etymology and usage notes: nonrelated is formed with the prefix non- and the adjective related. In many contexts, especially genetics, the term unrelated is more common, but nonrelated remains in use in general language and cross-disciplinary writing.