Cultural appropriation is a concept in sociology that refers to one culture being adopted by another. There is a heated debate about the authenticity of borrowed cultures but a very thin line that separates borrowing from stealing or outright desecrating. In the context of writing, this means that a writer from a certain community should be wary of writing about people from an unrelated community. This is extremely problematic for the writer and can be countered by doing adequate research on the subject or by using the crutch of imagination, which is after all the fulcrum of the novel-writing business.
Some articles about this controversial theme: