This is the 11024th most frequent Russian word.
генная
"Genetic" or "gene-related."
The word "генная" relates to "engineering" (инженерия), forming the phrase "генная инженерия" which means "genetic engineering".
Генная инженерия открывает новые возможности в медицине.
Genetic engineering opens new possibilities in medicine.
In this sentence, "генная" modifies "терапия", creating the compound "генная терапия" which means "gene therapy".
Генная терапия используется для лечения наследственных заболеваний.
Gene therapy is used to treat hereditary diseases.
Here "генной" describes "структуры", indicating "генной структуры", which translates to "genetic structures".