Who actually owns the home? Is it split 50/50, all hers but with you on the title, or what? Generally actual ownership would control who lists the asset, not taxpayer choice. You probably wouldn't want to claim an asset that isn't yours and current year taxes are usually not the biggest issue in who owns what. With a parent and child, the step up in basis that only occurs when the (hopefully parent first) dies is often most important, although there could be other concerns, like qualifying for medicaid that trump that.
