A first-degree relative (FDR) is a person's parent (father or mother), full sibling (brother or sister) or child. It constitutes a category of family members that largely overlaps with the term
nuclear family
A nuclear family, elementary family, cereal-packet family or conjugal family is a family group consisting of parents and their children (one or more), typically living in one home residence. It is in contrast to a single-parent family, the larg ...
, but without spouses.
If the persons are
related by blood, the first degree relatives share approximately 50% of their genes. First-degree relatives are a common measure used to diagnose risks for common diseases by analyzing family history.
See also
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Second-degree relatives
A second-degree relative (SDR) is someone who shares 25% of a person's genes. It includes uncles, aunts, nephews, nieces, grandparents, grandchildren, half-siblings, and double cousins.
See also
*Family
*First-degree relative
*Third-degree rela ...
*
Third-degree relatives
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Family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
*
Next of kin
A person's next of kin (NOK) are that person's closest living blood relatives. Some countries, such as the United States, have a legal definition of "next of kin". In other countries, such as the United Kingdom, "next of kin" may have no legal d ...
References
Family
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