Molecular Bases of Response to Copper Treatment in Menkes Disease, Related Phenotypes, and Unexplained Copper Deficiency

* INCLUSION CRITERIA: In order to be eligible to participate in this study, an individual must meet all of the following criteria: 1. Provision of signed and dated informed consent form by parent or legal guardian, or the subject himself/herself. 2. Male or female, aged 0 to 80 years. 3. Diagnosed with classic Menkes disease, Occipital Horn Syndrome (OHS), or unexplained copper deficiency. 4. Serum copper level results between 0 and 75 mg/dl (normal range 80-180 microgram/dl). 5. Ability to adhere to the prescribed subcutaneous Copper Histidinate injection regimen. 6. Willingness to comply with all study visits and procedures. EXCLUSION CRITERIA: An individual who meets any of the following criteria will be excluded from participation in this study: 1. Pre-existing liver (e.g., hepatitis, biliary atresia, cirrhosis) or kidney disease (e.g., serum creatinine \>1.0 mg/dL) 2. History of bleeding diatheses 3. Pregnancy or lactation 4. Diagnosis of Wilson disease 5. Any disease or condition that, in the opinion of the Investigator, has a high probability of precluding the patient from completing the study or where the patient cannot or will not appropriately comply with study requirements 6. Participation in any other investigational trial in which receipt of investigational drug or device occurred within 30 days prior to screening for this study 7. History of diagnosed drug or alcohol dependence within the previous 3 years 8. Any disease process that may adversely affect gastrointestinal absorption, e.g. celiac sprue 9. Chronic/severe cardiac disease (applies to adult subjects only) that could make participating in a clinical trial physically demanding, including but not limited to cardiac insufficiency, arrhythmias, bradycardia, or hypotension, unless associated with other features of dysautonomia, as in OHS. 10. History of cerebrovascular accident (applies to adult subjects only) that could make participating in a clinical trial difficult for the subject. Adults who are, or who may be, unable to consent will not be allowed to participate in this study. This is because we did not encounter subjects in this category for whom enrollment would be necessary or appropriate in our previous studies (90-CH-0149, 90-N-0149) with this IND. The main populations to be recruited are 1) pediatric subjects under 18 years of age with inherited copper transport disorders, and 2) non-cognitively-impaired adults with unexplained copper deficiency. NIH employees are eligible to participate in this protocol if they meet the Inclusion criteria and have no exclusion criteria. Recruitment, enrollment and compensation of NIH employee subjects will be consistent with the Guidelines for the Inclusion of Employees in NIH Intramural Research Studies (December 2015) and NIH Policy Manual Chapter 2300-630-3, "Leave Policy for NIH Employees Participating in NIH Medical Research Studies". The consenting research team member will make the NIH Information Sheet on Employee Research Participation available to staff members who are considering enrolling. If the individual requesting to participate in the protocol is a co-worker, the consent from the NIH staff member (co-worker) will not be obtained by the staff member s direct supervisor but by another research staff member approved for obtaining informed consent who is not a co-worker. Neither participation nor refusal to participate as a subject in this protocol will have an effect, either beneficial or adverse, on the participant s employment or position at NIH. Employee subjects' privacy and confidentiality will be respected by protocol and consenting staff the same as for all subjects participating in research protocols. However, all subjects will be made aware that there are limits to these protections.