A relationship by blood: siblings are closely consanguinous; cousins, and grandparents and grandchildren, less so. (See INBREEDING.)
The birth of o?spring to parents who are closely related (see CONSANGUINOUS). In traditional rural communities, marriage between cousins was common and this could lead to a higher-than-average number of children with congenital anomalies or learning diffculties. This is now seen in certain ethnic groups who have brought the custom of inbreeding with them to their new homes in the western world.... inbreeding
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