Gender identity disorder (GID) is a rare disorder and is defined as the condition in which a person has a strong feeling of identification with the opposite sex. They have discomfort with the biological or anatomical sex that they were born with. A person born as a male (biological male with male genitals) may feel and acts like a girl and a biological female may feel and act like a boy. They have strong desire to live like the members of the opposite sex, and may dress and behave like the other gender.
Gender identity disorder may be seen in children or adults.