A CLINICAL AND BIOCHEMICAL-STUDY OF HEREDITARY HEMOCHROMATOSIS IN SAGUENAY LAC-SAINT-JEAN (QUEBEC)

The authors have analyzed the clinical and biochemical data collected in 30 families with hereditary hemochromatosis (HH) from Saguenay Lac- Saint-Jean. The clinical manifestations of HH were similar to those pr eviously described. However, the mean age at diagnosis of the probands was much lower than usually reported (36 versus 50 years) and was ass ociated with a greater severity at a young age; this was particularly true for 7 inbred probands compared to non-inbred probands. Percent tr ansferrin saturation was the best biochemical indicator of genotype in the families studied while ferritin appeared to be an indicator of pr ogress of the disease. Our results suggest that the high variability i n the biochemical abnormalities and the age at onset and severity of t he clinical signs in the HH homozygotes are the result not only of mut ation variability, but also, at least partially, of the action of modi fying genes and/or other genes involvedd in iron metabolism.