Probably most notable case is https://en.wikipedia.org/wiki/Brandon_Teena (the story was made into the movie Boys Don't Cry). You can find quite a few more on https://en.wikipedia.org/wiki/List_of_unlawfully_killed_tran....

It's the second part of his question that's the important one -- lots of people are murdered for lots of different reasons. There are estimated to be over a million trans people in the USA, do they have a disproportionately high rate of murder?

I can't find conclusive numbers on murders specifically. http://time.com/3999348/transgender-murders-2015/ says:

> Though a federal hate crimes law requires the collection of some statistics related to violence against transgender people, experts are dubious about the numbers they're getting. “A lot of jurisdictions report zeroes, even in places where we know there are hate crimes," Keisling says. Most state laws don't require the collection of such statistics, according to Minter.

Given the high incidence of sexual violence against transgender persons (https://www.ovc.gov/pubs/forge/sexual_numbers.html) it certainly seems likely the murder rate is similarly high. There's a "one-in-twelve" stat that appears to have gone around, but it's not true: http://www.politifact.com/texas/statements/2015/may/13/garne...