[The hemochromatosis gene (HFE). Molecular analysis--diagnostic applications]. / Le gène de l'hémochromatose (HFE). Analyse moléculaire--applications diagnostiques.

Hemochromatosis is the most common single gene disorder in Caucasian populations. Regulation of iron balance by intestine is impaired, leading to a widespread deposition of iron, and the disease is associated with an increased risk of hepatocellular carcinoma. Typically the excess of iron treated by phlebotomies is performed in our Blood Center. In 1996 an original paper identifying HFE as a strong candidate gene for hemochromatosis was published and two mutations were described (C282Y and H63D). The former results in a cysteine to tyrosine substitution at amino acid 282 and was found in different patient populations up to 80-90% of patients homozygous for the C282Y mutation. The frequency of the second variant H63D is also increased in hemochromatosis patients but its penetrance is probably not complete. Assessing clinical implications is a new way of identifying patients at risk for this frequent and probably underdiagnosed disease, and important because treatment by venesections is safe with a proven benefit in preventing development of the disease. Four hundred and eighty patients were included in our study and we have shown in this work a correlation between the genotype and the phenotypic presentation of the disorder, with patients homozygous for the C282Y mutation having a greater excess of iron.

[Reconstruction of orbital floor fractures using autologous materials]. / Reconstruction du plancher orbitaire fracturé par des matériaux autologues.

Bone and Cartilage Autograft gather all the necessary qualities for an interpositional material to be used in the fractured orbital floor reconstruction, leading to the binocular vision recovery and in term of tolerance. The initial material choice depends on the clinic and orbital tomodensitometry datas, but the final decision is made on the operating findings. However, schematic indications can be drawn up, depending on material characteristics, curve, rigidity and resorption degree, and fracture particularities.