Genetic Study of Severe Zinc Deficiencies

Inclusion Criteria: * Are included all patients (minors included) with suggestive symptoms and biological signs of a hereditary deficiency of zinc, appeared for the first time at birth or weaning (see description given in the introduction); * Clinical diagnosis of zinc deficiency must be made by a specialist dermatologist, pediatrician or gastroenterologist; * Zinc deficiency has been audited by an assay of serum zinc, erythrocyte, plasma, urine or hair; * The response of all symptoms and signs to zinc oral supplementation should be rapid and complete. Exclusion Criteria: * All patients with homozygous or compound heterozygous mutations in the SLC39A4 gene are excluded because they have a proven acrodermatitis enteropathica (AE); * All patients who developed their first symptoms of zinc deficiency outside the neonatal period, most likely because they have an acquired deficiency and not congenital; * All patients with probable cause of zinc deficiency that is surgery of the digestive tract, chronic digestive disease, or total parenteral nutrition.