A Transgender individual is someone who feel they are the opposite gender of what they appear to be on the outside.Their brains think as a women but they have a male genitalia or vise versa. 
There has also been research done to show that transgender individuals brain does think as they sex they wish to be.People think it is disgusting but if you think about it it's not disgusting at all.They are still the same person inside just changed to what they feel inside to the outside.If they are male and think as a women they are a woman.They just have surgery to fix their parts and it's not disgusting at all. There is also nothing in the bible that goes against transgendered people at all. If you are transgendered you are not automatically gay,you can be,but that is your orientation not you're sex. 
Sex=hormones,sex organs
Gender=what society views how man and woman should look.
If you like men and are male who feels female you are straight but if you are a male who likes woman you are a lesbian. I think a lot of people say it's disgusting because they want to know what they are getting and don't want to have to be surprised,but you're not.If the person who are with identifies as female they are female and you are straight,not gay.Besides some transgendered females look more female than some generic woman do. :)
According to Dr. Jillian T. Weiss of the Bilerico Project, we should scrap the word "Transgendered" all together because since they want to be accepted as the sex they identify with it's calling them out in a way.
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