According to the World Health Organization classification, a living donor has one of the following relationships with the recipient:
A1. Genetically related
- 1st degree genetically related: e.g. parent, sibling offspring
- 2nd degree genetically related, e.g. grandparent, grandchild, aunt, uncle, niece, nephew
- Other than 1st or 2nd degree genetically related, e.g. cousin
A2. Emotionally related, e.g. spouse, (if not genetically related, in-law, adopted, friend).
B. Unrelated: not genetically or emotionally related