diff --git a/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunction1DAdapter.h b/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunction1DAdapter.h
index b8287d0db88366222105785a2a50771a48d88a43..9616b0811913e179af71028f47637e1fc134fd1a 100644
--- a/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunction1DAdapter.h
+++ b/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunction1DAdapter.h
@@ -41,8 +41,8 @@ namespace PythonInterface {
  * This is essentially a transparent layer that handles the function calls up
  *into Python.
  */
-class IFunction1DAdapter : public API::ParamFunction,
-                           public API::IFunction1D,
+class IFunction1DAdapter : public virtual API::ParamFunction,
+                           public virtual API::IFunction1D,
                            public IFunctionAdapter {
 public:
   /// A constructor that looks like a Python __init__ method
@@ -62,7 +62,6 @@ public:
 
 private:
   /// The PyObject must be supplied to construct the object
-  DISABLE_DEFAULT_CONSTRUCT(IFunction1DAdapter)
   DISABLE_COPY_AND_ASSIGN(IFunction1DAdapter)
 
   /// Flag if the functionDeriv1D method is overridden (avoids multiple checks)
diff --git a/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunctionAdapter.h b/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunctionAdapter.h
index 30479217d156ce155cd019e22bcc89b07082a1da..8118fe2b4867a3e878e1d1ea0582763c2a059066 100644
--- a/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunctionAdapter.h
+++ b/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IFunctionAdapter.h
@@ -106,7 +106,6 @@ protected:
 
 private:
   /// The PyObject must be supplied to construct the object
-  DISABLE_DEFAULT_CONSTRUCT(IFunctionAdapter)
   DISABLE_COPY_AND_ASSIGN(IFunctionAdapter)
 
   /// The name of the function
diff --git a/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IPeakFunctionAdapter.h b/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IPeakFunctionAdapter.h
index 4103d443e1e70de88e2f95818e8ff7faafb412fa..9db1bee7f03a8f82af7f16e3d265618ad3fb3047 100644
--- a/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IPeakFunctionAdapter.h
+++ b/Framework/PythonInterface/inc/MantidPythonInterface/api/FitFunctions/IPeakFunctionAdapter.h
@@ -87,7 +87,6 @@ public:
 
 private:
   /// The PyObject must be supplied to construct the object
-  DISABLE_DEFAULT_CONSTRUCT(IPeakFunctionAdapter)
   DISABLE_COPY_AND_ASSIGN(IPeakFunctionAdapter)
 };
 }