Prevalence of a Non-Expressing 11B Mutation in Aka Peoples of the Central African Republic

Sponsor
National Institute of Environmental Health Sciences (NIEHS) (NIH)
Overall Status
Completed
CT.gov ID
NCT00340769
Collaborator
(none)
0
3
68.1
0
0

Study Details

Study Description

Brief Summary

The CCCH tandem zinc finger proteins are members of a small family of proteins that regulate the stability of certain types of mRNA containing so-called class II AU-rich elements in their 3'-untranslated regions. The best studied member of this protein family, tristetraprolin (TTP), exerts this destabilizing effect on at least two mRNAs coding for physiologically and medically important cytokines, tumor necrosis factor alpha and granulocyte macrophage colony stimulating factor. The physiological functions of the other two members of this protein family in mammals, 11B and 11D, are not known, but in experimental transfection studies they too can destabilize mRNAs containing this type of AU-rich element.

As part of the Environmental Genome Project, we resequenced the protein coding portions of the human genes encoding these three proteins, and uncovered a dinucleotide splice site mutation in the 11B gene in one of 144 alleles sequenced. We showed that this mutation created a novel restriction fragment length polymorphism, and that this mutation resulted in the failure of splicing and expression of the mRNA encoded by the mutant allele. Based on our previous data with mice completely deficient in TTP, we anticipate that complete deficiency of this protein, and possibly its partial deficiency, would result in human disease.

The mutant allele was from an anonymous adult Aka Pygmy women from the Central African Republic. We propose to genotype up to 1000 members of this ethnic group after obtaining buccal cell DNA from them. This will give us an approximate idea of the prevalence of this mutation in this population. If the mutation is found in a significant number of living individuals in this initial screen, then we will propose a later study of the individuals who have this genotype and their families. This second study, which will be reviewed separately, will attempt to correlate this genotype with a human trait or phenotype and possible y treatable human disease.

Condition or Disease Intervention/Treatment Phase

    Detailed Description

    The CCCH tandem zinc finger proteins are members of a small family of proteins that regulate the stability of certain types of mRNA containing so-called class II AU-rich elements in their 3'-untranslated regions. The best studied member of this protein family, tristetraprolin (TTP), exerts this destabilizing effect on at least two mRNAs coding for physiologically and medically important cytokines, tumor necrosis factor alpha and granulocyte macrophage colony stimulating factor. The physiological functions of the other two members of this protein family in mammals, 11B and 11D, are not known, but in experimental transfection studies they too can destabilize mRNAs containing this type of AU-rich element.

    As part of the Environmental Genome Project, we resequenced the protein coding portions of the human genes encoding these three proteins, and uncovered a dinucleotide splice site mutation in the 11B gene in one of 144 alleles sequenced. We showed that this mutation created a novel restriction fragment length polymorphism, and that this mutation resulted in the failure of splicing and expression of the mRNA encoded by the mutant allele. Based on our previous data with mice completely deficient in TTP, we anticipate that complete deficiency of this protein, and possibly its partial deficiency, would result in human disease.

    The mutant allele was from an anonymous adult Aka Pygmy women from the Central African Republic. We propose to genotype up to 1000 members of this ethnic group after obtaining buccal cell DNA from them. This will give us an approximate idea of the prevalence of this mutation in this population. If the mutation is found in a significant number of living individuals in this initial screen, then we will propose a later study of the individuals who have this genotype and their families. This second study, which will be reviewed separately, will attempt to correlate this genotype with a human trait or phenotype and possible treatable human disease.

    Study Design

    Study Type:
    Observational
    Official Title:
    Prevalence of a Non-Expressing 11B Mutation in Aka Peoples of the Central African Republic
    Study Start Date :
    Apr 18, 2001
    Study Completion Date :
    Dec 20, 2006

    Outcome Measures

    Primary Outcome Measures

      Eligibility Criteria

      Criteria

      Ages Eligible for Study:
      N/A and Older
      Sexes Eligible for Study:
      All
      Accepts Healthy Volunteers:
      Yes
      • ELIGIBILITY CRITERIA:

      Both genders are eligible.

      Ages included children through adulthood.

      Must be willing and able to participate and understand the explanations and instructions.

      Contacts and Locations

      Locations

      Site City State Country Postal Code
      1 NIEHS, Research Triangle Park Research Triangle Park North Carolina United States 27709
      2 Washington State University Vancouver Washington United States 98686
      3 Ministry of Health and Scientific Research Bangui Central African Republic

      Sponsors and Collaborators

      • National Institute of Environmental Health Sciences (NIEHS)

      Investigators

      None specified.

      Study Documents (Full-Text)

      None provided.

      More Information

      Publications

      None provided.
      Responsible Party:
      , ,
      ClinicalTrials.gov Identifier:
      NCT00340769
      Other Study ID Numbers:
      • 999901160
      • 01-E-N160
      First Posted:
      Jun 21, 2006
      Last Update Posted:
      Jul 2, 2017
      Last Verified:
      Dec 20, 2006

      Study Results

      No Results Posted as of Jul 2, 2017