Vitamin D Metabolism and the Williams Syndrome


The Williams syndrome is a disease in which supravalvular aortic stenosis, an elfin facies, mental retardation and other congenital defects are sometimes associated with abnormal vitamin D and calcium metabolism. Whereas some patients have been reported to show increased sensitivity to vitamin D or an exaggerated response of serum 25-hydroxyvitamin D {25(OH)D} to administration of vitamin D and to have hypercalcemia caused by increased circulating 1,25-dihydroxyvitamin D{1,25(OH)2D} in infancy and early childhood, most patients have normal calcium metabolism and normal values for circulating 25(OH)D and 1,25(OH)2D. We propose to carry out further studies of vitamin D metabolism to elucidate the mechanism(s) for abnormal vitamin D metabolism. We will determine the response of serum 1,25(OH)2D to administration of 1,25(OH)2D3. Measurement of the 1,25(OH)2D in the patients compared to normal subjects will be the primary outcome.

Study Type

  • Study Type: Observational
  • Study Design


  • Drug: Vitamin D

Participating in This Clinical Trial

Age 18 years to 50 years of age, patients and normal subjects

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: 50 Years

Are Healthy Volunteers Accepted: Accepts Healthy Volunteers

Investigator Details

  • Lead Sponsor
    • National Center for Research Resources (NCRR)

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