Be in the genes
Definition 1 of 1
Pro Tip 1/3Inherited Traits
Refers to qualities or abilities passed down from parents to children through genes. 
She has a talent for singing – it’s in the genes, as her mother was a vocalist.
Pro Tip 2/3Not Learned
Indicates an ability or trait not gained from experience or education, but from family inheritance. 
Even without training, he's a fast runner. It must be in the genes.
Pro Tip 3/3Figurative Use
Often used to suggest a trait is so strong it seems inherited, even if it’s not scientifically proven. 
Her passion for justice is in her genes, much like her grandfather.