The fact that there appears to be a genetic component to inflammatory bowel disease, but that it does not show clear Mendelian i
nheritance ratios suggests any of the following, EXCEPT: the gene for the disease has incomplete penetrance. the gene for the disease has limited expressivity. the disease is polygenic. the gene for the disease is recessive.
(the gene for the disease has incomplete penetrance. the gene for the disease has limited expressivity. the disease is polygenic) - all these are examples of non-mendelian inheritance which include incomplete penetrance, polygenic inheritance etc. These do not follow the mendelian pattern of inheritance.
(the gene for the disease is recessive.)- this shows the mendelian pattern of inheritance... Dominant and recessive characteristics are examples that show Mendelian inheritance.
