Vitamin D Binding Protein (Gc) Allele Variation Effects Response to Vitamin D Treatment

Vitamin D Status Clinical Trial

— Gc  

Official title:

Vitamin D Binding Protein (Gc) Allele Variation Effects Response to Vitamin D Treatment

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00650780
• Other study ID #: Creighton4
• Status: Completed
• Phase: N/A
• First received: March 30, 2008
• Last updated: April 1, 2008
• Start date: October 2007
• Est. completion date: January 2008

Study information

• Verified date: March 2008
• Source: Creighton University
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

We have just completed a randomized, clinical trial of 100,000 IU Vitamin D3 given as a single dose at the beginning of winter. We found a wide range of responses to the dose. This study proposes that genetic differences account for some of the variation in response of 25(OH)D levels after treatment with oral Vitamin D.

Description:

We suspect that the wide range of response is effected by other factors such as variation in Vitamin D binding protein (the major transporter of Vitamin D metabolites).

Gc, also known as Vitamin D binding protein (DBP), group specific component, or Gc globulin, is a 52-58 kDa multifunctional plasma protein, synthesized in the liver. The gene encoding for Gc is located on chromosome 4, and three common co-dominant alleles give rise to three phenotypes (Gc1s, Gc1f, and Gc2). Gc binds actin, recruits neutrophil leukocytes and converts into a macrophage- and osteoclast- activating factor. It also is the major transporter of Vitamin D and its' metabolites. Lauridsen et al. showed that Gc phenotype correlates with 25(OH)D levels in a group of postmenopausal women.

This study proposes that Gc phenotype accounts for some of the variation in response of 25(OH)D levels after treatment with oral Vitamin D.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 29
• Est. completion date: January 2008
• Est. primary completion date: January 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 19 Years to 90 Years

Eligibility

Inclusion Criteria:

• Must be willing to participate with an additional blood draw.

• Must have been in the previous study.

Exclusion Criteria:

• Will not be eligible if not a part of the previous study

Study Design

Observational Model: Cohort, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Vitamin D Status

Locations

Country	Name	City	State
United States	Creighton University	Omaha	Nebraska

Sponsors (1)

Lead Sponsor	Collaborator
Creighton University

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Gc concentration and phenotype		at 1st visit	No