Iron Deficiency Anem. Practically all cases of iron deficiency are due to lack of intake of iron in the diet or loss of iron through bleeding (gi tract or menstruation, for example). There are many diseases, while not common, that can result in iron deficiency anemia as an affect of the underlying disorder and some can be inherited. These would include inherited malabsorption diseases, hemolysis, & hemoglobinurias.
Familial iron . I have seen that trend in several families but no gene have been identified yet. Lot of times members of same family have same eating habits, possibility of malabsorption syndromes, vitamin deficiencies and occupational or environmental hazards which predispose them to risk of iron def. Also colon cancer and polyposis syndromes can run in families and can present as iron def as a common symptom.