16th International HLA and Immunogenetics Workshop : Liverpool : 28th May - 3rd June 2012

Projects

Global Distribution of Extended HLA Haplotypes

Medhat Askar, Marcelo Fernandez-Vina

Objectives:
This workshop component aims at characterization and studying the distributions of extended HLA haplotypes (A, C, B, MICA, DRB1, DRB3/4/5, DQA1, DQB1, DPA1, and DPB1) among different ethnic populations. These haplotypes will be identified through family studies conducted historically in the context of related donor searches (mainly HSCT but also solid organs when available) in participating laboratories. This study is open to laboratories from all over the world including different ethnicities that are less represented in HSC donor registries.

Methods:

  • Index subjects carrying haplotypes identified by family studies in families with known ethnicity will be further typed to high resolution and untyped loci (DQB1, DQA1, DRB3/4/5, DPB1, DPA1, MICA): Typing can be performed at the participating labs or at the Cleveland Clinic at no cost
  • Identified haplotypes that reach a specific threshold (e.g. top 10th percentile, appear in 3 independent families, etc) will be tested for prevalence  in unrelated donors tested in participating labs and individuals who appear to have no mismatches to these haplotypes will be (DQB1, DQA1, DRB3/4/5, DPB1, DPA1, MICA)

Phases & Timeline

This project has four phases (Laboratories may elect to participate in one or more of the project phases):

  1. Laboratories can submit informative cases by contacting the coordinators of the project and by providing (June –Nov 2011):
    • a. HLA typing of all tested family members of informative cases
    • b. Ethnic origin of these cases.
    • c. Records of any subjects typed in the same lab and appear to have this haplotypes in their genotype along with their ethnic origin.
  2. Workshop testing of genomic DNA for HLA (Dec 2011 -Feb 2012).
    • a. Index subjects carrying haplotypes identified by family studies in families with known ethnicity will be further typed to high resolution and untyped loci (DQB1, DQA1, DRB3/4/5, DPB1, DPA1, MICA): Typing can be performed at the participating labs or at the Cleveland Clinic at no cost
    • b. Identified haplotypes that reach a specific threshold (e.g. top 10th percentile, appear in 3 independent families, etc) will be tested for prevalence in unrelated donors tested in participating labs and individual appear to have no mismatches to these haplotypes will be (DQB1, DQA1, DRB3/4/5, DPB1, DPA1, MICA)
    • c. Submit results which will be incorporated into the project database.
  3. Data analysis (March-May 2012):
    • a. The project database will be made available to participants who wish to analyze the data.
    • b. Appropriate statistical methods will be applied to calculate haplotypes frequencies in different ethnic populations
  4. The group will prepare a workshop component report for publication.

Current Particpants:
Current participants in this project form the USA include;

  • Children’s Hospital of Philadelphia, PA
  • Cleveland Clinic, OH
  • Mayo Clinic, MN
  • North Western University, IL
  • Rush University, IL
  • St. Jude’s Hospital, TN
  • St. Vincent Hospital, IN
  • Stanford, CA
  • University of Cincinnati, OH
  • University of Michigan, MI
  • University of North Carolina, NC
  • University of Pennsylvania, PA
  • Wake Forest University, NC

and from the other countries we have:

  • Australian Red Cross
  • Hammad Medical Corporation, Qata
  • Mansura University, Egypt
  • Military Hospital in Riyadh, Saudi Arabia
  • Nagoya University, Japan
  • New Zealand Blood Service, New Zealand
  • Sheikh Khalifa Medical City, United Arab Emirates
  • University of Alberta, Canada

Contacts:
Please let us know if you would like to participate in the workshop.  We will provide you with further information as the project proceeds.

Download a PDF of the BSHI 2011 Presentation - download PDF file.

Download a PDF of the ASHI 2011 Presentation - download PDF file.

Nov 10, 2011 Posted by Admin