#unilateral_descent  line of descent traced through one side of the family
  supertype:  line_of_descent__descent__lineage__filiation  the kinship relation between an individual and the individual's progenitors
  subtype:  matrilineage__enation__cognation  line of descent traced through the maternal side of the family
  subtype:  patrilineage__agnation  line of descent traced through the paternal side of the family

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