Adult Male Character Obsessive-Compulsive Disorder medicine.medical_specialty Tryptophan Hydroxylase medicine.disease_cause Polymorphism, Single Nucleotide Young Adult Reference Values Polymorphism (computer science) Internal medicine Humans Medicine Obsessive compulsive symptoms perfectionism genetics Young adult Association (psychology) Gene Genetic Association Studies Biological Psychiatry Defense Mechanisms TPH2 Receptors, Dopamine D2 business.industry Perfectionism (psychology) Psychiatry and Mental health Endocrinology Dopamine receptor Female Gene-Environment Interaction business Clinical psychology