Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to African iron overload ?
    ### Response:
    African iron overload was first noted in rural central and southern African populations among people who drink a traditional beer brewed in uncoated steel drums that allow iron (a component of steel) to leach into the beer. However, not all individuals who drink the beer develop African iron overload, and not all individuals of African descent with iron overload drink the beer.
    