Loss of shinobi abilities after overusage of Mangekyou Sharingan When a shinobi overuses the mangekyou sharingan, other than the vision (blindness), does he lose any other abilities as well? If so, what are they?
I was also wondering for a bit as well as I do know that it eventually makes the user blind which leads them to snatching the eyes from a blood relative Sharingan user. Whether that impacts their abilities is something I wasn't sure of. 

But, fret not, now I am!

Once Mangekyou Sharingan has been awakened, it grants them a lot nice extra's, but also the negative effect of turning blind over time. As far as I could find, the only negative effect is blindness, meaning that they retain their abilities from their eyes. Of course, it might be a bit difficult to cast Amaterasu accurately based on the sound of footsteps when you're blind, but that is essentially what is possible. 

When they awaken the eternal variant, they can unlock eventually what they had with their original eyes. Meaning that in the end, they gain a lot more.

So in short to answer your question, no, you don't. You only lose your sight unless you have the eternal variant.

Source: Naruto Wikia - Mangekyō Sharingan