hey, noor
you are choosing very good fields. your choices btw neuroscience and genetics are not that far apart yet, each has compelling reasons why you should do.My point of view, as medical student, i have taken both courses, i thought neuroscience was more enjoyable interms of doing things practically plus brain as it is, very fascinating, learning all the tracts and how they communicate with each other.
depending on where you live, as geneticist or neuroscientist , you can work as professor,in a lab, as consultant(my professor was post doc in this field and worked as consultant)
I will say, go for neuroscience very challenging indeed, but rewarding.
good luck!