ärvanliga

ärvanliga is a Swedish term used informally to describe traits or conditions that are commonly inherited within families or populations. The word combines ärva (to inherit) with vanlig (common). It is not an established technical label in genetics, but it appears in popular science writing and everyday language to signal a familial or genetic component in a characteristic.

In formal genetics, scientists prefer terms such as hereditary, genetic, or familial. The concept encompasses traits arising from single-gene (Mendelian) inheritance as well as polygenic architectures influenced by many genetic variants, often with environmental modifiers. Heritability estimates quantify how much of the observed variation in a population is due to genetic differences, and they do not determine outcomes for individuals.

Examples frequently discussed as “ärvanliga” include eye color and blood type, which show strong hereditary patterns, and certain disorders such as some inherited metabolic or blood disorders. Traits like height are highly heritable in part but also strongly affected by nutrition and other environmental factors, illustrating that inheritance does not equal inevitability.

Limitations and caveats: being "ärvanlig" in a population sense does not guarantee that every family member will express the trait, and a trait can be common without being strongly inherited if environmental factors play a large role or if the trait is influenced by population history.

See also: heredity, heritability, genetic inheritance.