How do I specialize member functions based on the base class of the templated class

I'm trying to specialize member functions of a template class based on the type of template. In particular I'd like to have specializations based on polymorphic types. I've been struggling with the syntax. Here is my try which obviously produces the error: two or more data types in declaration of 'doSomething'

class Base {}
class Derived : public base {}

template<typename T>
class MyClass
{
public:

  void doSomething();

}

template<>
template<typename T>
typename std::enable_if<std::is_base_of<Derived, T>::value>::type
void MyClass<T>::doSomething() 
{
    // Do something with Derived type
}

template<>
template<typename T>
typename std::enable_if<std::is_base_of<Base, T>::value &&
                       !std::is_base_of<Derived, T>::value>::type
void MyClass<T>::doSomething() 
{
    // So something with Base type
}

template<>
template<typename T>
typename std::enable_if<!std::is_base_of<Derived, T>::value>::type
void MyClass<T>::doSomething() 
{
    // Do something with all other types
}

What would be the correct syntax?