Zinc deficiency in achondroplastic children and their parents

Abstract

Using atomic absorption spectrophotometry, we have assayed zinc and copper concentrations in the hair of children with typical achondroplasia, familial short stature, or constitutional growth delay, and of unaffected parents of achondroplastic children and healthy adults of similar age and sex as the parents (Table). Specimens consisted of the terminal 2 to 3 inches of hair, obtained from the posterior scalp. Duplicate 60 to 80 mg hair specimens were digested in concentrated nitric:perchloric (3:1) acid mixture. The results are the mean of at least two determinations per specimen. The achondroplastic children were all confirmed as typical examples by physical examination and radiographs of skull, spine, long bones, and pelvis. Several of the parents were noted to have white flecks in their fingernails, which has been reported to be associated with zinc deficiency. The data indicate significantly reduced zinc and increased copper values, and reduced zinc:copper ratio, in the hair of parents and children with achondroplasia.