Modern observation, by intense attention to externals, finds causes and relative facts. Useful though these may be, there are superficial and deeper causes for everything. So genes do not ultimately cause or determine anything, rather they are in the realm of secondary causes and effects. Behind and through them are undiscovered dimensions.
It is the same with brain and body. There are causes that run far deeper than genes and brain patterns. The light bulb in our ceiling may be considered the source of the light, or one may look to the generator, the waterfall, the Sun, or a “big bang.” But then science cannot truly define gravity or thought and the origin of the universe is not contained in the pages of books.