Oddly enough, I was diagnosed with Klinefelter Syndrome AFTER I began my transition.
When it came time for me to donate sperm pre-HRT, I was found to be infertile, and a Karyotype test was done as standard procedure, which flagged up the syndrome.
In general I simply refer to myself as transgendered. I had already began to see myself as trans before my diagnosis, and really, I feel comfortable enough identifying as trans without having to add this into the equation of explaining myself in my day to day life.
But if people choose to enquire further as to my condition, and reasoning behind my trans nature, I will often take the time to tell them about my inter-sexed condition.
I believe that it is a key aspect of my trans nature, but like others have said, being inter-sexed and being trans are not mutually exclusive, so I try not to rely on my genetics to explain away everything.
At the end of the day, the way I see it, being inter-sexed may be one of the causes of my being trans, but my genetics are not what people see when they look at me, they see a trans person, so why bother trying to apply another label to yourself? It just complicates and already complicated matter

Hope that helps >.>