سعید ناصری - Dept of Molecular Biology, Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran
رحیم سروری زنجانی - Baqiyatallah University of Medical Sciences, Tehran, Iran and, Zanjan University of Medical Sciences, Zanjan, Iran
زهرا پور پاک - Dept of Immunology, Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran
نیما رضایی - Dept of Immunology, Immunology, Asthma and Allergy Research Institute and Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
مصطفی معین - Dept of Immunology, Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran
نیما پروانه - Dept of Infectious Diseases, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
اصغر آقا محمدی - Section of Immunology and Allergy, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran

Correlation of Null Btk Expression and Gene Noncoding Mutations in XLA Patients Nasseri S۱, Sorouri R۲, Pourpak Z۳, Rezaei N۴, Moin M۵, Parvaneh N۶, Aghamohammadi A۷ ۱ Dept of Molecular Biology, Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran ۲ Baqiyatallah University of Medical Sciences, Tehran, Iran and, Zanjan University of Medical Sciences, Zanjan, Iran ۳ Dept of Immunology, Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran ۴ Dept of Immunology, Immunology, Asthma and Allergy Research Institute and Childrenchr('۳۹')s Medical Center, Tehran University of Medical Sciences, Tehran, Iran ۵ Dept of Immunology, Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran ۶ Dept of Infectious Diseases, Childrenchr('۳۹')s Medical Center, Tehran University of Medical Sciences, Tehran, Iran ۷ Section of Immunology and Allergy, Childrenchr('۳۹')s Medical Center, Tehran University of Medical Sciences, Tehran, Iran Corresponding Authorchr('۳۹')s Address: Section of Immunology and Allergy, Childrenchr('۳۹')s Medical Center, Tehran University of Medical Sciences, Tehran, Iran E-mail: aghamohammadi@sina.tums.ac.ir Received: ۲۰ July, ۲۰۰۸ Accepted: ۲۹ Dec, ۲۰۰۸ Background and Objective: X-linked agammaglobulinemia (XLA) is a primary immunodeficiency disorder characterized by recurrent bacterial infections, profound lack of serum antibodies and reduced circulating B lymphocytes. Mutations in Bruton´s tyrosine kinase gene (BTK) result in XLA. It is shown that absence of Btk protein expression may be accompanied by no mutations in coding regions in some cases, instead alterations in conserved regulatory domains of promoter and the first intron of BTK gene maybe occurred. The aim of this study was evaluation of Btk expression and mutation analysis in coding and regulatory regions of the gene. Materials and Methods: In this study, eleven XLA patients were enrolled. Btk expression was analyzed by western immunoblotting method. Mutation analysis was carried out in eight patients. In three cases, PCR of the regulatory regions was performed with designed primers, followed by sequencing. Results: According to western blot, normal Btk expression in three patients and null expression in eight others was observed. Mutation analysis showed two novel BTK mutations in two patients (۱۰۳۸-۱۰۴۰ delAGG and IVS۸-۲delA). No coding or regulatory region mutations were found in three cases with null Btk expression. Conclusion: Based on these results, three cases with null expression and had no coding or regulatory region mutations are interesting. It is possible that some rare regulatory defects may have been occurred, other than conventional sites. This must be taken into account for future investgations.

Key words: Btk, Noncoding mutation, Agammaglobulinemia