A transgender person is one who has the role of the gender to which he belongs, this means that he could have been born with a masculine body, but he believes he is a woman and that is when he begins to acquire a behavior of the feminine gender. This also applies to the contrary, when he is born with a female body and thinks he is a man.
Therefore, when a person thinks that his body is not what his mind tells him, he is considered transgender and this process begins at an early age, when the child tells his parents that he is not a child but a girl or vice versa.
This type of person, when his appearance changes, can become heterosexual, homosexual or bisexual, in the gender in which he is considered.