No one had expected the penetrance to be so low and predictably the results were greeted with considerable skepticism. In attempting to reconcile our data with the concept that the homozygous state had a much higher penetrance it was suggested that the data were flawed in a number of respects. It was proposed that we were dealing with an unusually healthy population or population with an extraordinarily healthy life style. Alternatively it was proposed that our population was unusually sickly and that the manifestations of hemochromatosis had been obscured by the poor health of the controls. Obviously it is impossible to reconcile these two objection the population cannot be too well and too sickly at the same time. But in fact neither criticism applies. The most cogent objection was that our study was biased by selecting a healthy population. If indeed patients with symptoms had been excluded because they did not attend a health appraisal clinic having died or being taken care of in a more intense medical setting we might have erroneously concluded that the penetrance of the homozygous state is very low. But there is a straightforward way to address this problem. If homozygotes were systematically excluded then the number found in the population should fall short of the number predicted by the Hardy-Weinberg equilibrium based on the gene on the gene frequency in the population. But in fact the number of homozygotes actually exceeds the predicted number Another way to examine the possible lethal effect of