genetic; hereditary
Used in scientific, medical, or general contexts to describe traits, diseases, or characteristics passed down through genes.
This disease has strong genetic factors.
Some traits are determined genetically.
先天的 means 'congenital' or 'innate', present from birth but not necessarily genetic. 遺伝的 specifically refers to genetic inheritance.
Compound of 遺伝 (iden, 'heredity') + 的 (-teki, '-like, -ic'). 遺伝 is composed of 遺 (i, 'leave behind') and 伝 (den, 'transmit').