diff --git a/gramps/gen/lib/person.py b/gramps/gen/lib/person.py
index af4d500f1..63e83101a 100644
--- a/gramps/gen/lib/person.py
+++ b/gramps/gen/lib/person.py
@@ -99,7 +99,7 @@ class Person(CitationBase, NoteBase, AttributeBase, MediaBase,
         self.parent_family_list = []
         self.alternate_names = []
         self.person_ref_list = []
-        self.gender = Person.UNKNOWN
+        self.__gender = Person.UNKNOWN
         self.death_ref_index = -1
         self.birth_ref_index = -1
         if data:
@@ -136,7 +136,7 @@ class Person(CitationBase, NoteBase, AttributeBase, MediaBase,
         return (
             self.handle,                                         #  0
             self.gramps_id,                                      #  1
-            self.gender,                                         #  2
+            self.__gender,                                       #  2
             self.primary_name.serialize(),                       #  3
             [name.serialize() for name in self.alternate_names], #  4
             self.death_ref_index,                                #  5
@@ -181,7 +181,7 @@ class Person(CitationBase, NoteBase, AttributeBase, MediaBase,
             "_class": "Person",
             "handle":  Handle("Person", self.handle),            #  0
             "gramps_id": self.gramps_id,                         #  1
-            "gender": self.gender,                               #  2
+            "gender": self.__gender,                             #  2
             "primary_name": self.primary_name.to_struct(),       #  3
             "alternate_names": [name.to_struct() 
                                 for name in self.alternate_names], #  4
@@ -276,7 +276,7 @@ class Person(CitationBase, NoteBase, AttributeBase, MediaBase,
         """
         (self.handle,             #  0
          self.gramps_id,          #  1
-         self.gender,             #  2
+         self.__gender,           #  2
          primary_name,            #  3
          alternate_names,         #  4
          self.death_ref_index,    #  5
@@ -675,7 +675,9 @@ class Person(CitationBase, NoteBase, AttributeBase, MediaBase,
                        - Person.UNKNOWN
         :type gender: int
         """
-        self.gender = gender
+        if gender not in (Person.MALE, Person.FEMALE, Person.UNKNOWN):
+            raise ValueError('Attempt to assign invalid gender')
+        self.__gender = gender
 
     def get_gender(self) :
         """
@@ -688,7 +690,10 @@ class Person(CitationBase, NoteBase, AttributeBase, MediaBase,
                   - Person.UNKNOWN
         :rtype: int
         """
-        return self.gender
+        return self.__gender
+
+    gender = property(get_gender, set_gender, None,
+                      'Returns or sets the gender of the person')
 
     def set_birth_ref(self, event_ref):
         """