de novo pathogenic variants

Definition of de novo variant

de novo variant

(deh NOH-voh VAYR-ee-unt)
A genetic alteration that is present for the first time in one family member as a result of a variant (or mutation) in a germ cell (egg or sperm) of one of the parents, or a variant that arises in the fertilized egg itself during early embryogenesis. Also called de novo mutation, new mutation, and new variant.

Source: NCI Dictionary of Cancer Terms