Skip to main content
padlock icon - secure page this page is secure

Free Content Carrier Frequency of a Nonsense Mutation in the Adenosine Deaminase (ADA) Gene Implies a High Incidence of ADA‐deficient Severe Combined Immunodeficiency (SCID) in Somalia and a Single, Common Haplotype Indicates Common Ancestry

Download Article:

You have access to the full text article on a website external to Ingenta Connect.

Please click here to view this article on Wiley Online Library.

You may be required to register and activate access on Wiley Online Library before you can obtain the full text. If you have any queries please visit Wiley Online Library

Summary

Inherited adenosine deaminase (ADA) deficiency is a rare metabolic disorder that causes immunodeficiency, varying from severe combined immunodeficiency (SCID) in the majority of cases to a less severe form in a small minority of patients. Five patients of Somali origin from four unrelated families, with severe ADA‐SCID, were registered in the Greater London area. Patients and their parents were investigated for the nonsense mutation Q3X (ADA c7C>T), two missense mutations K80R (ADA c239A>G) and R142Q (ADA c425G>A), and a TAAA repeat located at the 3′ end of an Alu element (AluVpA) positioned 1.1 kb upstream of the ADA transcription start site. All patients were homozygous for the haplotype ADA‐7T/ADA‐239G/ADA‐425G/AluVpA7. Among 207 Somali immigrants to Denmark, the frequency of ADA c7C>T and the maximum likelihood estimate of the frequency of the haplotype ADA‐7T/ADA‐239G/ADA‐425G/AluVpA7 were both 0.012 (carrier frequency 2.4%). Based on the analysis of AluVpA alleles, the ADA c7C/T mutation was estimated to be approximately 7,100 years old. Approximately 1 out of 5 – 10000 Somali children will be born with ADA deficiency due to an ADA c7C/T mutation, although within certain clans the frequency may be significantly higher. ADA‐SCID may be a frequent immunodeficiency disorder in Somalia, but will be underdiagnosed due to the prevailing socioeconomic and nutritional deprivation.
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Document Type: Research Article

Affiliations: 1: Department of Forensic Genetics, Institute of Forensic Medicine, University of Copenhagen, DK-2100 Copenhagen, Denmark 2: Regional Molecular Genetics, Great Ormond Street Hospital NHS Trust, Great Ormond Street, London WC1N 3JH, United Kingdom 3: Molecular Immunology Unit, Institute of Child Health, 30 Guilford Street London WC1N 1EH, United Kingdom

Publication date: May 1, 2007

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more