Second-degree relative

A second-degree relative (SDR) is someone who shares 25% of a person's genes. It includes uncles, aunts, nephews, nieces, grandparents, grandchildren, half-siblings, and double cousins.[1][2][3]

See also

• Family
• First-degree relative
• Third-degree relative

References

1. "Breast and Ovarian Cancer and Family History Risk Categories". Center for Disease Control.
2. "First, Second and Third Degree Relative". Blue Cross Blue Shield.
3. "NCI Dictionary of Genetics Terms". Cancer.gov.