Abstract
Several cell types from male infants with Menkes disease accumulate increased amounts of copper. Ultrastructural localization of copper by a histologic staining technique and X-ray microanalysis established the subcellular distribution of the metal. In Menkes patients, copper was heavily concentrated on the brush border of intestinal epithelium as well as on the plasma membrane of cultured fibroblasts. The transport defect seems to be caused by a decreased transport of copper across plasma membranes, which mainly affects the influx mechanism.