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Background and Objective: Occult hepatitis B infection is a form of hepatitis in which despite of absence of detectable HBsAg, HBV-DNA is present in peripheral blood of patients. The mechanisms which are responsible for progression of OBI yet to be clarified but some investigators believed that the genetics and immunological parameters may are different in resistant individuals and patients. Cytokine network system could be leading alteration in viral immune response. The aim of this study was to investigate the relation between polymorphisms +874 region of IFN-Gama with occult hepatitis B infection. Materials and Methods: In this study, the plasma samples of 3700 blood donors were tested for HBsAg and anti-HBs by ELISA. The HBsAg negative and anti-HBc positive samples were selected and screened for HBV-DNA by PCR. HBV-DNA positive samples assigned as occult hepatitis B infection cases and ARMS-PCR technique were performed to examine the present polymorphisms in +874 region of IFN-Gama genes of patients with occult hepatitis B infection. Results: 352 (9.51%) out of 3700 blood samples were negative for HBsAg and positive for anti-HBc antibody. HBV-DNA was detected in 57 (16.1%) of HBsAg negative and anti-HBc positive samples. Our results showed that there was not any significant difference between patients and control group in polymorphisms in +874 region of IFN-Gama genes. Conclusion: This study showed that there is not any significant difference between polymorphisms in +874 region with IFN-Gama occult hepatitis B infection.

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Neurofibromatosis type1 (NF1) with the incidence of 1 in 3500 births, is the most common disorder which affects skin and peripheral nervous system. NF1 results from mutations in NF1 gene. The NF1 gene spans 350kbp and to date, nearly 2434 mutations in it were reported. The gene with 100 percent penetrance is located on chromosome 17 encoding neurofibromin protein. Recently, many challenges of its genetic analysis have been overcome through the application of new sequencing techniques. In present study patients with neurofibromatosis type 1 have been characterized from clinical symptoms such as presence of café au lait spot, plexiform neurofibroma, optic nerves involvement, presence of several patients in first degree relatives. These patients were in different ages including 73, 63, 44, 20 with different symptoms and severities of disease. In this communication, a NF1 family with 4 cases in 3 generations has been presented.

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Fibrodysplasia ossificans progressiva (FOP) is an extremely rare autosomal dominant disorder having variable expressivity with complete penetrance. FOP incidence has been estimated to be 1 per 2 million. FOP caused by mutations in ACVR1 gene encoding bone morphogenetic protein type-1 receptor. To date, 15 types of mutations have been reported. The majority of cases were determined to be the rsult of a new mutation occuring sporadically. Here we report a 20 years old girl who's suffering FOP for 11 years.

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Background and Objective: Duplex PCR is a widespread molecular biology technique that has the ability in specific and high sensitivity detection of microorganisms. This study was performed to evaluate the molecular identification of Pseudomonas stutzeri using duplex PCR.
Methods: In this descriptive-laboratory study, Pseudomonas stutzeri ATCC 17588 bacteria was purchased from genetic resources center and after culturing the bacteria, DNA was extracted in the exponential growth phase using boiling method. Duplex PCR was carried out for specific identification of the bacteria subsequently. The primers were designed using catA and nirP gene sequences. Sensitivity and specificity of duplex PCR technique were investigated using 5 bacteria.
Results: The amplification of two bands of 512 bp and 249 bp for catA and nirP genes were observed, respectively. The specificity was 100% .The sensitivity of 0.048 ng/µL of genomic DNA was determined for catA and nirP genes, respectively.
Conclusion: Duplex-PCR molecular method with its sensitivity and proper feature and high potential for identification of Pseudomonas bacteria can be applied as a routine method in well-equipped laboratories by expert technician to identify suspicious cases.