If she deeded the house to you in 2010, then it was considered a gift to you in 2010.
Your basis in the home would be the price she paid for the house, plus improvements she made, or the Fair Market Value (FMV), whichever is lower.
This can be a huge difference. Then the house would need to be shown as a sale of 2nd residence and would be subject to capital gain tax.
EDITED 3/5/2017
If the house actually passed to you on death, then the value of the house for tax purposes is date of death. So you get a stepped up basis, which most of the time will significantly reduce the gain you may have on the sale. This is a major difference in most cases.
Here is the response to a somewhat similar answer a few days ago, that may be helpful.
https://ttlc.intuit.com/questions/3747223
