Inanç Değer Fidancı1, Bülent Zülfikar2, Kaan Kavaklı3, M Cem Ar4, Yurdanur Kılınç5, Zafer Başlar6, Server Hande Cağlayan1. 1. Boğaziçi University, Department of Molecular Biology and Genetics, İstanbul, Turkey. 2. İstanbul University Medical School, Institute of Oncology, İstanbul, Turkey. 3. Ege University Medical School, Department of Pediatric Hematology, İzmir, Turkey. 4. İstanbul Training and Education Hospital, Department of Hematology, İstanbul, Turkey. 5. Çukurova University Medical School, Department of Pediatric Hematology, Adana, Turkey. 6. İstanbul University Cerrahpaşa Medical Faculty, Department of Internal Medicine, Division of Hematology, İstanbul, Turkey.
Abstract
OBJECTIVE: A severe complication in the replacement therapy of hemophilia A (HA) patients is the development of alloantibodies (inhibitors) against factor VIII, which neutralizes the substituted factor. The primary genetic risk factors influencing the development of inhibitors are F8 gene mutations. Interleukins and cytokines that are involved in the regulation of B-lymphocyte development are other possible targets as genetic risk factors. This study assesses the possible involvement of 9 selected single nucleotide gene polymorphisms (SNPs) with interleukins (IL-4, IL-5, and IL-10), transforming growth factor beta 1 (TGF-β1), and interferon gamma (IFN-γ) in inhibitor development in severely affected HA patients carrying a null mutation in the F8 gene. MATERIALS AND METHODS: A total of 173 HA patients were screened for intron 22 inversion and null mutations (nonsense and deletions). Genotyping of a total of 9 SNPs in genes IL-4, IL-5, IL-10, TGF-β1, and IFN-γ in 103 patients and 100 healthy individuals was carried out. RESULTS: An association analysis between 42 inhibitor (+) and 61 inhibitor (-) patients showed a significant association with the T allele of rs2069812 in the IL-5 gene promoter and patients with inhibitors (p=0.0251). The TT genotype was also significantly associated with this group with a p-value of 0.0082, odds ratio of about 7, and confidence interval of over 90%, suggesting that it is the recessive susceptibility allele and that the C allele is the dominant protective allele. CONCLUSION: The lack of other variants in the IL-5 gene of patients and controls suggests that rs2069812 may be a regulatory SNP and may have a role in B-lymphocyte development, constituting a genetic risk factor in antibody development.
OBJECTIVE: A severe complication in the replacement therapy of hemophilia A (HA) patients is the development of alloantibodies (inhibitors) against factor VIII, which neutralizes the substituted factor. The primary genetic risk factors influencing the development of inhibitors are F8 gene mutations. Interleukins and cytokines that are involved in the regulation of B-lymphocyte development are other possible targets as genetic risk factors. This study assesses the possible involvement of 9 selected single nucleotide gene polymorphisms (SNPs) with interleukins (IL-4, IL-5, and IL-10), transforming growth factor beta 1 (TGF-β1), and interferon gamma (IFN-γ) in inhibitor development in severely affected HA patients carrying a null mutation in the F8 gene. MATERIALS AND METHODS: A total of 173 HA patients were screened for intron 22 inversion and null mutations (nonsense and deletions). Genotyping of a total of 9 SNPs in genes IL-4, IL-5, IL-10, TGF-β1, and IFN-γ in 103 patients and 100 healthy individuals was carried out. RESULTS: An association analysis between 42 inhibitor (+) and 61 inhibitor (-) patients showed a significant association with the T allele of rs2069812 in the IL-5 gene promoter and patients with inhibitors (p=0.0251). The TT genotype was also significantly associated with this group with a p-value of 0.0082, odds ratio of about 7, and confidence interval of over 90%, suggesting that it is the recessive susceptibility allele and that the C allele is the dominant protective allele. CONCLUSION: The lack of other variants in the IL-5 gene of patients and controls suggests that rs2069812 may be a regulatory SNP and may have a role in B-lymphocyte development, constituting a genetic risk factor in antibody development.
Entities:
Keywords:
Association study; F8 gene mutation; Hemophilia A; Inhibitor formation; Interleukins/cytokines; Single nucleotide gene polymorphisms
Authors: M E Eyster; J H Lewis; S S Shapiro; F Gill; M Kajani; D Prager; I Djerassi; S Rice; C Lusch; A Keller Journal: Am J Hematol Date: 1980 Impact factor: 10.047