Dietary Cholesterol and Defects in Cholesterol Synthesis in Mevalonate Kinase Deficiency

Participants are admitted to the clinical research center for up to a week per visit. Additional visits at least yearly encouraged. During the week we measure such things as cholesterol absorption, sterol and bile acid synthesis, mevalonate and mevalonate shunt products, isoprenoids, fatty acids, leukotrienes, plasma cholesterol and other sterol levels. Also, the effects of altering dietary cholesterol on plasma 24-S OH-cholesterol, a measure of brain cholesterol turnover, will be evaluated. Studies of body composition/ metabolism/ growth, development, behavior, sleep, feeding, hearing and vision will be carried out to document the phenotype and determine if dietary intervention may be helpful. The objective of the study is to characterize the metabolic and phenotypic consequences of MKD and study the effects of altering dietary cholesterol in MKD. We hypothesize that some of the phenotypic effects of MKD are due to altered cholesterol metabolism, but that the phenotype is predominantly due to derangements in isoprenoid metabolism.