11.   There are conflicting opinions on what causes the disease.

12.   Recent research shows that the disease is caused in part by bad nutrition.

13.   Scientists have isolated the gene that causes the disease.

14.   Many diseases are caused by parasites.

15.   One sect of medical researchers holds the minority view that the disease is not caused by that virus.

16.   This goes some way towards typing the organism causing the disease.

17.   How many of these organisms cause disease?

18.   Many single gene inherited diseases are caused by mutations which affect hepatic function, including haemophilia, phenylketonuria, and many of the disorders of cholesterol metabolism.

19.   As the different alcoholic beverages have not been shown to cause different diseases it is possible that alcohol itself is the most harmful component of the beverages.