The HLA rs9267649 and CYP24A1 rs2248359 Variants are Associated with Multiple Sclerosis: A Study on Iranian Population.

Background: Studies have shown that MS results from synergism between genetic and environmental factors. As a genetic factor, the rs9267649 variant through the regulatory effect on the HLA-DRB1 expression is involved in the MS development. In addition, vitamin D deficiency through involvement of rs2248359 variant of CYP24A1 has shown to play important role in the risk of MS. Objectives: The aim of this study was to investigate both the HLA rs9267649 and CYP24A1 rs2248359 variants with risk of multiple sclerosis (MS) in Iranian population. Materials and Methods: The rs9267649 and rs2248359 variants were genotyped in 82 Iranian Relapsing-Remitting Multiple Sclerosis (RRMS) patients and 100 matched healthy controls, using the PCR-RFLP method. The genotype and allele frequencies were calculated and statistically analyzed. Results: A significant difference was found in the allele distribution for the both rs9267649 and rs2248359 variants, such that the A allele of rs9267649 and the C allele of rs2248359 were found to be more frequent in MS patients than in the healthy controls (p-value: 0.009, OR: 2.264, 95% CI: 1.211-4.231 and p-value: 0.028 OR: 1.594, 95% CI: 1.052-2.415), respectively. Conclusions: The present research results provide further evidence on the association of the two variants rs9267649 of the HLA and rs2248359 of the CYP24A1 gene with MS etiology and an increased risk of MS in Iranian RRMS patients. However, further large-scale investigations in various ethnicities and in the functional genomics level are demanded to confirm our findings.

Increased Mitochondrial DNA Copy Number and Oxidative Damage in Patients with Hashimoto's Thyroiditis.

BACKGROUND: The purpose of present study was to investigate mitochondrial DNA copy number (mtDNAcn) and mtDNA damage in peripheral blood of patients with Hashimoto's thyroiditis (HT) and healthy controls (HC). METHODS: The relative mtDNAcn and oxidative DNA damage in this case-control study were measured in peripheral blood of 50 patients with Hashimoto's thyroiditis and 50 healthy controls using quantitative real-time PCR. The study was conducted in Tehran University of Medical Sciences hospital, Tehran, Iran in 2018. RESULTS: HT patients had significantly higher mitochondrial DNA copy number and mitochondrial oxidative damage than the comparison group. CONCLUSION: These data suggest the possible involvement of mitochondria and oxidative stress in the pathophysiology of HT.

Analysis of MicroRNA-18a Expression in Multiple Sclerosis Patients.

BACKGROUND: In multiple sclerosis (MS), the immune system acts against myelin lesions of the central nervous system, destroying neuronal fibers resulting in signal transmission disturbances in the nervous system. MicroRNAs play important roles in the post-transcriptional regulation of gene expression and in the regulation of disease activity and its response to treatment. The goal of this study was to determine the role of miR-18a-5p by comparing its expression in MS patients and healthy subjects. METHODS: RNA was isolated from blood samples of 32 MS patients and 32 healthy individuals, and miR-18a-5p expression was determined by real-time polymerase chain reaction (real-time PCR). RESULTS: miR-18a-5p expression was significantly less in MS patients than in healthy subjects. CONCLUSION: The reduction of miR-18a-5p expression may be via pathway signaling. Altered signaling plays an important role in MS pathogenesis and the miR-18a-5p expression profile in blood cells can be described as a prognostic biomarker and identifier of high-risk individuals in MS.

Quantification of mitochondrial DNA damage and copy number in circulating blood of patients with systemic sclerosis by a qPCR-based assay

Abstract Background: Although not fully understood, oxidative stress has been implicated in the pathogenesis of different autoimmune diseases such as systemic sclerosis. Accumulating evidence indicates that oxidative stress can induce mitochondrial DNA (mtDNA) damage and variations in mtDNA copy number (mtDNAcn). Objective: The aim of this study was to explore mtDNAcn and oxidative DNA damage byproducts in peripheral blood of patients with systemic sclerosis and healthy controls. Methods: Forty six patients with systemic sclerosis and forty nine healthy subjects were studied. Quantitative real-time PCR used to measure the relative mtDNAcn and the oxidative damage (oxidized purines) of each sample. Results: The mean mtDNAcn was lower in patients with systemic sclerosis than in healthy controls whereas the degree of mtDNA damage was significantly higher in cases as compared to controls. Moreover, there was a negative correlation between mtDNAcn and oxidative DNA damage. Study limitations: The lack of simultaneous analysis and quantification of DNA oxidative damage markers in serum or urine of patients with systemic sclerosis and healthy controls. Conclusion: These data suggest that alteration in mtDNAcn and increased oxidative DNA damage may be involved in the pathogenesis of systemic sclerosis.

Quantification of mitochondrial DNA damage and copy number in circulating blood of patients with systemic sclerosis by a qPCR-based assay.

BACKGROUND: Although not fully understood, oxidative stress has been implicated in the pathogenesis of different autoimmune diseases such as systemic sclerosis. Accumulating evidence indicates that oxidative stress can induce mitochondrial DNA (mtDNA) damage and variations in mtDNA copy number (mtDNAcn). OBJECTIVE: The aim of this study was to explore mtDNAcn and oxidative DNA damage byproducts in peripheral blood of patients with systemic sclerosis and healthy controls. METHODS: Forty six patients with systemic sclerosis and forty nine healthy subjects were studied. Quantitative real-time PCR used to measure the relative mtDNAcn and the oxidative damage (oxidized purines) of each sample. RESULTS: The mean mtDNAcn was lower in patients with systemic sclerosis than in healthy controls whereas the degree of mtDNA damage was significantly higher in cases as compared to controls. Moreover, there was a negative correlation between mtDNAcn and oxidative DNA damage. STUDY LIMITATIONS: The lack of simultaneous analysis and quantification of DNA oxidative damage markers in serum or urine of patients with systemic sclerosis and healthy controls. CONCLUSION: These data suggest that alteration in mtDNAcn and increased oxidative DNA damage may be involved in the pathogenesis of systemic sclerosis.

Gene Panel Testing in Hereditary Breast Cancer.

BACKGROUND: Breast cancer (BC) is a highly complex, heterogeneous and multifactorial disease and is the most commonly diagnosed cancer and the leading cause of cancer-related mortality in women worldwide. Family history and genetic mutations are important risk factors for BC. While studies in twins have estimated that about 10%-30% of BC are due to hereditary factors, only 4%-5% of them are due to mutations in BRCA1 or BRCA2 genes. Our aim was to investigate the role of other BC genes in familial BC among the Iranian population. METHODS: We selected 61 BC patients who were wild-type for BRCA1 and BRCA2 mutations but who met the criteria for hereditary BC based on the American College of Medical Genetics and Genomics (ACMG) and the National Comprehensive Cancer Network (NCCN) guidelines. We performed targeted sequencing covering the exons of 130 known cancer susceptibility genes based on the Cancer Gene Census list. RESULTS: We found seven mutations in seven known BC susceptibility genes (RAD50, PTEN, TP53, POLH, DKC1, WRN and CHEK2) in seven patients including two pathogenic frameshift variants in RAD50 and WRN genes, four pathogenic missense variants in TP53, PTEN, POLH, and DKC1 genes and a pathogenic splice donor variant in the CHEK2 gene. The presence of all these variants was confirmed by Sanger sequencing and Gap reverse transcription-polymerase chain reaction (RT-PCR) for the splice variant. In silico analysis of all of these variants predicted them to be pathogenic. CONCLUSION: Panel testing of BC patients who met the established criteria for hereditary BC but who were negative for BRCA1/2 mutations provided additional relevant clinical information for approximately 11.5% of the families. Our findings indicate that next generation sequencing (NGS) is a powerful tool to investigative putative mutagenic variants among patients who meet the criteria for hereditary BC, but with negative results on BRCA1/2 testing.

TIM-3 genetic variants and risk of Behçet disease in the Iranian population.

BACKGROUND: Behçet disease is a prototypical systemic autoimmune disease, caused by a complex interplay between environmental and genetic factors. The transmembrane immunoglobulin and mucin domain-3 (TIM-3) is a distinct member of the TIM family that is preferentially expressed on Th1 cells and plays a role in Th1-mediated autoimmune or inflammatory diseases, such as Behçet disease. OBJECTIVE: The aim of this study was to test the potential association between TIM-3 gene polymorphisms and Behçet disease. METHODS: Two single-nucleotide polymorphisms of TIM-3 (rs9313439 and rs10515746) were genotyped in 212 patients with Behçet disease and 200 healthy controls. Typing of the polymorphisms was performed using multiplex PCR amplification. RESULTS: There were no significant differences in allele and genotype frequencies between the Behçet disease patients and controls who were successfully genotyped. Similar results were also found after stratification by gender, age, or clinical features. STUDY LIMITATIONS: Lack of studies on various racial or ethnic groups and small sample size. CONCLUSION: This study failed to demonstrate any association between the tested TIM-3 polymorphisms and Behçet disease.

TIM-3 genetic variants and risk of Behçet disease in the Iranian population

Abstract: Background: Behçet disease is a prototypical systemic autoimmune disease, caused by a complex interplay between environmental and genetic factors. The transmembrane immunoglobulin and mucin domain-3 (TIM-3) is a distinct member of the TIM family that is preferentially expressed on Th1 cells and plays a role in Th1-mediated autoimmune or inflammatory diseases, such as Behçet disease. Objective: The aim of this study was to test the potential association between TIM-3 gene polymorphisms and Behçet disease. Methods: Two single-nucleotide polymorphisms of TIM-3 (rs9313439 and rs10515746) were genotyped in 212 patients with Behçet disease and 200 healthy controls. Typing of the polymorphisms was performed using multiplex PCR amplification. Results: There were no significant differences in allele and genotype frequencies between the Behçet disease patients and controls who were successfully genotyped. Similar results were also found after stratification by gender, age, or clinical features. Study limitations: Lack of studies on various racial or ethnic groups and small sample size. Conclusion: This study failed to demonstrate any association between the tested TIM-3 polymorphisms and Behçet disease.

Analysis of partial AZFc (gr/gr, b1/b3, and b2/b3) deletions in Iranian oligozoospermia candidates for intracytoplasmic sperm injection (ICSI)

Background/aim: Infertility is a main health issue. The human Y chromosome contains essential genes for spermatogenesis, especially those located on four major intervals defined as AZFa, AZFb, AZFc, and AZFd. A partial deletion of the AZFc region is reported as a significant risk factor for oligo-/azoospermia. The main purpose of this study was to investigate the prevalence of partial deletions in the AZFc region (gr/gr, b1/b3, and b2/b3) in Iranian oligozoospermic candidates for intracytoplasmic sperm injection. Materials and methods: Multiplex PCR was used to assess the micro and partial deletions in 60 oligozoospermia infertile and 80 fertile men. Results: Two cases (3.33%) showed AZFb deletion but no microdeletion was detected in the control samples. In the AZFc region, 20% of the patients showed deletions, in which 15% and 5% showed gr/gr and b2/b3 deletions, respectively. However, 10% of the healthy individuals also showed partial deletions, including gr/gr (7.5%) and b2/b3 (2.5%). No significant correlation was detected between the presence of gr/gr microdeletion in patients and controls (P > 0.05). Conclusion: Our study showed that the partial AZFc deletions are not associated with male infertility in Iranian subjects.

The protective role of TBX21-1514T>C polymorphism in susceptibility to multiple sclerosis.

Background: As a T-cell mediated disease, multiple sclerosis (MS) pathogenesis might be associated with the immune system and its involved genes. TBX21, which encodes T-bet transcription factor, is a critical regulator of the commitment to the Th1 lineage and Interferon gamma (IFNγ) production. Investigation of the association of -1514T > C polymorphism located upstream of TBX21 gene with MS susceptibility is reasonable due to its demonstrated significant association with some other immune-mediated diseases. Methods: We analyzed the genotype frequencies of -1514T > C polymorphism between 248 Iranian patients with MS and 163 matched healthy controls. By applying polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP)- technique, the single-strand conformation patterns of the amplicons were compared and sequenced. Results: Strong association between the wild -1514T allele and MS susceptibility was found with the allelic frequency of 99.6% in patients vs. 95.1% in controls (P = 0.002), and the CC genotype frequency of the TBX21 polymorphism (-1514T > C) reported potential protective effect against the disease (P = 0.014). Conclusion: The TBX21-1514T > C polymorphism confers possible protective effect on MS in Iranian population. Further comprehensive studies in different settings are required to clarify the exact role of TBX21 gene in MS disease.

MMP9 Gene Expression Variation by Ingesting Tart Cherry and P-Coumaric Acid During Remyelination in the Cuprizone Mouse Model.

Matrix metalloproteinase-9 (GELB) as a member of gelatinases plays key role in the destruction of blood-brain barrier (BBB), T cells migration into the CNS, and demyelination induction. Considering remyelination induction in response to tart cherry extract and pure p-coumaric acid ingestion via tracking MMP9 gene expression in the cuprizone mouse model. Firstly, predicting the chemical interaction between p-coumaric acid and MMP9 protein was conducted through PASS and Swiss dock web services. Next, the content of p-coumaric acid in the tart cherry extract was analyzed by HPLC. Later, mice (male, female) were categorized into two groups: standard, cuprizone. After the demyelination period, mice classified into four groups: standard, natural chow, tart cherry extract, p-coumaric acid. Finally, brains were extracted from the skull, and MMP9 gene expression was evaluated by real time RT-PCR. Bioinformatics analysis displayed p-coumaric acid has potent inhibitory effect on MMP9 gene expression (Pa=0.818) with estimated ΔG (kcal/mol) -8.10. In addition, during the demyelination period, MMP9 expression was increased significantly in the male group that is related to myelin destruction. However, MMP9 was declined throughout remyelination in both male and female. It's remarkable that pure p-coumaric acid and tart cherry extract ingestion could decrease the gene expression ratio more than natural chow. According to the results, it's deduced the male mouse is more appropriate gender for demyelination induction via cuprizone. In addition, tart cherry extract and pure p-coumaric acid ingestion could decrease MMP9 gene expression level considerably during remyelination.

In Silico Perspectives on the Prediction of the PLP's Epitopes involved in Multiple Sclerosis.

BACKGROUND: Multiple sclerosis (MS) is the most common autoimmune disease of the central nervous system (CNS). The main cause of the MS is yet to be revealed, but the most probable theory is based on the molecular mimicry that concludes some infections in the activation of T cells against brain auto-antigens that initiate the disease cascade. OBJECTIVES: The Purpose of this research is the prediction of the auto-antigen potency of the myelin proteolipid protein (PLP) in multiple sclerosis. MATERIALS AND METHODS: As there wasn't any tertiary structure of PLP available in the Protein Data Bank (PDB) and in order to characterize the structural properties of the protein, we modeled this protein using prediction servers. Meta prediction method, as a new perspective in silico, was performed to fi nd PLPs epitopes. For this purpose, several T cell epitope prediction web servers were used to predict PLPs epitopes against Human Leukocyte Antigens (HLA). The overlap regions, as were predicted by most web servers were selected as immunogenic epitopes and were subjected to the BLASTP against microorganisms. RESULTS: Three common regions, AA58-74, AA161-177, and AA238-254 were detected as immunodominant regions through meta-prediction. Investigating peptides with more than 50% similarity to that of candidate epitope AA58-74 in bacteria showed a similar peptide in bacteria (mainly consistent with that of clostridium and mycobacterium) and spike protein of Alphacoronavirus 1, Canine coronavirus, and Feline coronavirus. These results suggest that cross reaction of the immune system to PLP may have originated from a bacteria or viral infection, and therefore molecular mimicry might have an important role in the progression of MS. CONCLUSIONS: Through reliable and accurate prediction of the consensus epitopes, it is not necessary to synthesize all PLP fragments and examine their immunogenicity experimentally (in vitro). In this study, the best encephalitogenic antigens were predicted based on bioinformatics tools that may provide reliable results for researches in a shorter time and at a lower cost.

Role of Th1/Th2 cells and related cytokines in autoimmune hepatitis.

BACKGROUND/AIMS: Dysregulation of T cell response is thought to play an important role in the immunopathogenesis of autoimmune hepatitis. However, no consensus has yet been reached regarding the implications of a distinct T cell subset in the pathogenesis of this progressive liver disease. Therefore, T-bet and GATA-3 expression was examined in patients with autoimmune hepatitis (AIH) and in healthy controls. Moreover, the profile of Th1 (IFN-γ) and Th2 (IL-4) cytokine gene expression was analyzed. MATERIALS AND METHODS: Levels of mRNA transcripts were measured in peripheral blood mononuclear cells (PBMCs) using a two-step reverse transcription quantitative real-time polymerase chain reaction with SYBR Green. RESULTS: T-bet and IFN-γ mRNA expression was significantly higher in AIH patients compared to healthy controls (p<0.05), whereas no differences were observed for either GATA-3 or IL-4 mRNA expression (p>0.05). CONCLUSION: Alterations in the Th1/Th2 cell balance may be responsible for both disease progression and the resulting complications.

Association of New Putative Epitopes of Myelin Proteolipid Protein (58-74) with Pathogenesis of Multiple Sclerosis.

Multiple sclerosis (MS) is an autoimmune disease in which auto-reactive T cells react with self-antigens expressed in the central nervous system (CNS). The main cause of MS is unknown. Nonetheless, the most probable theory is based on molecular mimicry, which suggests that some infections can activate T cells against brain auto-antigens like myelin proteolipid protein (PLP) and initiate the disease cascade. This study is conducted to evaluate the activatory effects of PLP58-74 on T lymphocytes and humoral immunity. PLP58-74 was considered as an immunodominant epitope candidate of PLP using bioinformatics tools. Patients and healthy individuals' peripheral blood mononuclear cells (PBMCs) were treated with PLP58-74 and its proliferative effects were evaluated through assessing proliferating cell nuclear antigen (PCNA) gene expression changes by real time PCR and immunocytochemistry assay. Finally, the rate of CD4+ and CD8+ T cells were assessed by flowcytometry. ELISA was also performed to measure anti PLP58-74 antibody in patients' serum. PLP58-74 induced proliferation in patients' PBMCs while it did not influence PBMCs of healthy individuals. CD4+ T cells were the main activated cells in reaction to PLP58-74 which increased from 22% to 39.91%. In addition, immune assay showed threefold increase in specific anti PLP58-74 IgG in patients compared to healthy controls. Results showed that PLP58-74 can stimulate CD4+ T cells and humoral immunity. Therefore it seems that the epitopes of some microorganisms mimicking PLP such as PLP58-74 might have a potential role in the initiation of MS.

Disturbed Th1 and Th2 balance in patients with Graves' disease.

BACKGROUND AND METHODS: Graves' disease (GD) is a common autoimmune disorder that is primarily driven by malfunction of T lymphocytes, which influences the production of antibodies reacting with cellular and tissue components of the thyroid gland. The aim of this study was to determine the level of mRNA expression for the genes encoding T-bet and GATA3, as the master regulators of the T helper (Th)1 and Th2 differentiation, respectively together with Th1 (IFN-γ) and Th2(IL-4) cytokine mRNA expression. Relative quantification of T-bet, GATA3, IFN-γ and IL-4 transcripts in peripheral blood mononuclear cell (PBMCs) was conducted by real-time reverse transcriptase PCR (RT-PCR). Serum levels of IFN-γ and IL-4 were also determined by Enzyme-linked immunosorbent assay (ELISA). In comparison with the normal group, T-bet and IFN-γ mRNA expression levels were significantly up-regulated in the GD patients, while GATA3 and IL-4 mRNA expression levels were downregulated. In addition, a marked decrease in plasma IL-4 levels was observed in the GD group. IFN-γ levels were also higher in patients in comparison to the controls. Furthermore, a clear correlation between increased IFN-γ mRNA expression and IFN-γ (P<0.05) was revealed. These results indicate that a Th1/Th2 imbalance exists in GD, and it may be implicated in the pathogenesis of disease.

Expression and prognostic significance of bcl-2 and bax in the progression and clinical outcome of transitional bladder cell carcinoma.

OBJECTIVE: To evaluate the mRNA expression ratio of Bcl-2/Bax both in normal and tumoral bladder tissues of patients with transitional cell carcinoma (TCC) of bladder and investigate potential correlation between this expression ratio and clinical outcome. MATERIALS AND METHODS: In this experimental study, we used real time-PCR to investigate the expression of Bcl-2 and Bax both in normal and tumoral bladder tissues. The Bcl-2/ Bax expression ratio was determined in tumoral bladder tissues of patients with transitional cell carcinoma of the bladder (n=40) and correlation between expression ratios and the emergence of early relapses in a follow-up of 14-30 months was examined. RESULTS: Relapse-free time in 14/31 patients (45.16%) with Bcl-2/Bax>1 was shorter than 9 months (range of 2-9 months) with 5.7 months average median while 17/31 patients (54.84%) with Bcl-2/Bax<1 are currently relapse-free (14-30 months). Bcl-2 and Bax expression levels were not solely correlated with clinical outcome and progression of carcinogenesis. CONCLUSION: The mRNA expression ratio of Bcl-2/Bax in tumoral bladder tissues may serve as a significant prognostic indicator in predicting the clinical outcome in low grade non-invasive bladder cancer.

Inhibitor IκBα promoter functional polymorphisms in patients with multiple sclerosis.

The aim of this study is to investigate the association of IκBα promoter polymorphisms with the development of Multiple Sclerosis (MS) disease in Iranian population. One hundred and fifty patients with MS along with 150 unrelated healthy controls were enrolled in this study. The IκBα -881A/G (rs3138053), -826C/T (rs2233406) and -519C/T (rs2233408) polymorphisms were determined by the polymerase chain reaction/restriction fragment length polymorphism method. This study demonstrated that the genotype frequencies of IκBα -881A/G and -826T/T, and allele frequencies of IκBα-881G were significantly higher in patients with MS with respect to as compared to the controls. We also found that the estimated haplotype frequency of IκBα promoter -881G-826T-519C was significantly increased in the patient with MS in comparison with that of the healthy individuals. This study reveals that polymorphisms in the IκBα promoter (-881 A/G, -826 C/T) are strongly associated with the susceptibility of Iranian MS patients.

Expression patterns of Th1/Th2 transcription factors in patients with guttate psoriasis.

Many lines of evidence propose that psoriasis is a T cell-mediated disease where T cell activation is followed by secretion of inflammatory cytokines. To elucidate the functional state of T cells in guttate psoriasis, we analysed mRNA expression levels of T-bet and GATA-3 for Th1 and Th2 differentiation, respectively together with Th1 (IFN-γ) and Th2 (IL-4) cytokine mRNA expression. Relative quantification of T-bet, GATA-3, IFN-γ and Th2, and IL-4 transcripts in peripheral blood leukocytes (PBL) was conducted by real-time reverse transcriptase PCR (RT-PCR). Serum levels of IFN-γ and Th2 and IL-4 were also determined by ELISA. GATA-3 and IL-4 mRNA expression levels were lower in psoriatic patients as compared to normal healthy controls. The expression levels of T-bet and IFN-γ and Th2 genes were relatively similar in the patients and controls. In addition, a marked decrease in plasma IL-4 levels was observed in the psoriasis group, while no differences were observed with regard to levels of IFN-γ and Th2 between patients and normal subjects. Furthermore, a clear correlation between decreased IL-4 mRNA expression and IL-4 (P < 0.05) was revealed. These results suggested that altered balance between Th1 and Th2 cells transcription factor genes and they products may be implicated in the pathogenesis of psoriasis.

BAK, BAX, and NBK/BIK proapoptotic gene alterations in Iranian patients with ataxia telangiectasia.

INTRODUCTION: Ataxia telangiectasia (AT) is an autosomal recessive multisystem disorder characterized by variable immunodeficiency, progressive neurodegeneration, occulocutaneous telangiectasia, and an increased susceptibility to malignancies. This study was designed to study the role of proapoptotic BAK, BAX, and NBK/BIK genes in a group of patients with AT to elucidate the possible role of these genes in progression of malignancies in this disease. MATERIALS AND METHODS: Fifty Iranian patients with AT were investigated in this study. The entire coding regions of the BAK gene (exons 2-6), NBK/BIK gene (exons 2-5), and BAX gene (exons 1-7) were amplified using polymerase chain reaction (PCR). The PCR products were separated by 2% agarose gel electrophoresis, and all positive samples were verified by direct sequencing of PCR products using the same primers used for PCR amplification, BigDye chemistry, and Avent 3100 Genetic Analyzer following the manufacturer's instructions (Applied Biosystems). RESULTS: Eight of fifty Iranian AT patients (16%) exhibited a C > T transition in exon 2 (c342C > T) of the BAK gene, while none of the healthy controls had such alteration (P = 0.0001). Higher frequency of another nucleotide substitution in the noncoding region of exon 7 in BAX gene (6855G > A) was also identified in 68% of the patient group versus 24% in the controls (P < 0.0001). Sequence alteration in intronic region of the NBK/BIK gene IVS4-12delTC was observed in 52% of AT patients, which was significantly higher than 20% in the control group (P = 0.0023). Another variant IVS1146C > T in the intronic region of the BAX gene was found in 78% of patients, which was significantly higher than 10% in the controls (P < 0.0001). Frequency of alteration in intronic region of exon 3 of the BAX gene (IVS3 + 14A > G) was also significantly higher in the AT patients (P < 0.0001). DISCUSSION: Several alterations in the proapoptotic genes BAK, NBK/BIK, and BAX were found in our study, which could elucidate involvement of the mitochondrial pathway mediated apoptosis in accelerating and developing of cancers and in immunopathogenesis of AT. Such altered apoptosis in AT could play some roles in developing cancers in this group of patients.