We'd like to use analytics cookies to understand which symbols people look up, so we know what to research next. They are not used for advertising and we set none of them unless you say yes. What we store.
Two parallel lines joining a couple who are blood relatives.
Also known as: Double line between a couple, Two lines joining two people in a chart
Where the horizontal line joining a couple is doubled, the two are related by blood. It is recorded without comment because it changes the arithmetic of recessive inheritance, which is the whole reason the chart exists.
A doubled horizontal line joining two individuals, denoting that the couple are related by blood.
Contexts: Medicine
Recorded because it raises the probability that both partners carry the same recessive variant, which directly changes the inheritance risk the chart is drawn to assess.
A statement about recessive-variant probability in a family, not about any individual couple or child.
A clinical notation rather than a judgement. Cousin marriage is ordinary and legal in much of the world and historically common everywhere, and the chart records the fact because it is genetically relevant.
The double line states a genetic relationship. It carries no verdict about the marriage.
Two short parallel horizontal lines, one directly above the other, joining two shapes side by side.