Consanguine

Consanguine is an English term that can function as a noun or an adjective. As an adjective, it denotes being related by blood, sharing a common ancestor. Historically, it could also be used as a noun to refer to a person who is a blood relative, though this usage is now rare. The word derives from Latin consanguineus, from con- "together" and sanguis "blood", and is related to consanguinity and the adjective consanguineous.

In modern English, consanguine is largely literary or archaic. Writers most often use consanguineous to describe relatedness, or prefer terms such as blood relative or kin.

In genetics and anthropology, the concept of consanguinity is important when considering kinship and hereditary risk. Consanguineous marriages—the union of individuals who are closely related by blood—can increase the likelihood that both partners carry the same recessive allele, raising the risk of autosomal recessive disorders in offspring. Degree of relatedness varies: parent–child and full siblings share about 50 percent of alleles, while first cousins share about 12.5 percent.

Related terms include consanguinity, kinship, and inbreeding. The term consanguine is now largely superseded by consanguineous and by explicit descriptions of familial relationships.