Nature vs. Nurture

Our textbook mentions Berry, Poortinga, and Pandey's definition of cross-cultural psychology in the revised Handbook of Cross-Cultural Psychology - "the systematic study of relationships between the cultural context of human development and the behaviors that become established in the repertoire of individuals growing up in a certain culture". Now that I've begun to delve deep into the study of different aspects of psychology during the pursuit of my degree, I've really started to notice just how much a person's culture can have an effect on how they develop psychologically.
This topic makes me keep coming back to, above everything else, the famous "nature vs. nurture" debate. To me, if there's one thing that is truly both immensely frustrating and immensely fascinating at the same time, it's trying to apply this debate to all the various psychological phenomenons that I've learned about in the past year. It feels like just about everything can be viewed from both sides of the argument, theoretically at least.
Take, for example, a boy getting abused by his father growing up to become abusive to his son himself. From the nurture standpoint, it could be his home environment during childhood that influenced him in this way. From the nature standpoint, he may have inherited genes from his father that caused him to have a penchant for violence. This is a pretty simple example, of course, but I feel as if I play out both sides of this argument in my head all the time. That peculiar sense of fascination about what makes people feel, think, and act the way they do is one of the reasons why I love psychology, and want to pursue a career in it.
Now, back on the subject of cultural psychology. I feel that the topic of how someone's culture affects them psychologically is something that especially intrigues me - both in terms of the topic itself, and how it ties into "nature vs. nurture". Is it the general environment created by a particular person's culture that produces a particular effect on their development? Or could it be that some genetic links passed on from ancestors cause people from certain cultures to develop in certain ways? Though I know that "nature vs. nurture" may never have a definite answer - be it nature, nurture, or (the most likely case) a combination of both, I'm hoping that as I go through this course, my interest in what makes people turn out the way they do will continue to be explored.