Background: Occult hepatitis B infection (OBI) is a form of hepatitis in which there is an absence of detectable HBsAg, despite the presence of HBV-DNA in the peripheral blood of patients. It seems that non-effective or attenuated immune system responses against HBV lead to the development of OBI. Previous studies showed that the Fas/Fas ligand (FasL) system is an important death signaling pathway that is used by cytotoxic T lymphocytes to eradicate HBV from the liver.
Objectives: To investigate polymorphisms in the -670 region of the Fas gene in those with OBI.
Patients and Methods: The plasma samples from 3700 blood donors were tested for HBsAg and anti-HBs by ELISA. The HBsAg-/anti-HBc+ samples were selected and screened for HBV-DNA by PCR. Those with HBV-DNA were diagnosed as OBI and PCR-RFLP technique was performed to examine polymorphisms within their Fas gene.
Results: 352 (9.5%) of 3700 blood samples were HBsAg-/anti-HBc+. HBV-DNA was detected in 57 (16.1%) of 352 HBsAg-/anti-HBc+ samples. Therefore, 57 HBsAg-/anti-HBc+/HBV-DNA+ patients were diagnosed as OBI. Patient and control groups had no significant differences in terms of the studied polymorphisms.
Conclusions: The functional polymorphisms in the promoter region of Fas gene are not associated with OBI. Therefore, it may be concluded that polymorphisms at the -670 position of the Fas gene do not have any critical effects on the immune response against HBV in OBI.
- Implication for Health policy/practice/research/medical education:
The role of gene polymorphisms in patients with Hepatitis B virus infection is discussed in this study. Reading this article is suggested to all virolo¬gists, genetic specialists in the field of hepatology.
- Please cite this paper as:
Arababadi MK, Mohammadzadeh A, Pourfathollah AA, Kennedy D. Polymorphisms within Fas gene are not associated with occult HBV infection. Hepat Mon. 2011;11(1):23-26.
2011 Kowsar M.P.Co. All rights reserved.
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