This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
Hailey Hailey disease is characterized by defect in 
Select and explain. 
A. ATP2C1, B. ATP2A2, C. ATP2C2, D. ATP2A1
A: ATP2C1
Answer: A: ATP2C1 
Explanation: Hailey Hailey disease : ATP2C1 gene defect
Darier's disease : ATP2A2 gene defect