Mohammad Mehdi Heidari

Yazd University · Department of Biology

Background: B-cell acute lymphoblastic leukemia (B-ALL) is a complex disorder that includes multiple genetic changes, one of the main causes of which is rare and common chromosomal translocations that lead to abnormal gene fusions. This abnormal fusion produces a new protein that causes the leukemia cells. These types of rearrangements usually occu...

Background Recently, new and advanced techniques have been adopted to design and produce nanobodies, which are used in diagnostic and immunotherapy treatments. Traditionally, nanobodies are prepared from camelid immune libraries that require animal treatments. However, such approaches require large library sizes and complicated selection procedures...

Introduction: Brain tumors are considered to be one of the most dangerous types of cancer, despite decades of research and treatment efforts. The activation of the telomerase enzyme is a critical factor in the immortality of these cells. Mutations in the promoter region of the TERT gene, particularly in the promoter hot spots, can influence the bin...

Programmed cell death protein-1 (PD-1) is a membrane protein expressed on the surface of activated T-cells, B-cells, natural killer cells, dendritic cells, macrophages, and monocytes. Inhibition of the PD-1/PD-L1 interaction by monoclonal antibodies (mAbs) has many therapeutic benefits and has led to a major advance in the treatment of various type...

Background Congenital heart disease (CHD) is the most prevalent developmental defect and principal cause of infant mortality and affects cardiac and large blood vessel structures in approximately 1% of live births worldwide. To date, numerous studies have related critical genetic dysfunctions to the pathogenesis of CHDs. However, the genetic basis...

Introduction: Familial adenomatous polyposis (FAP) is a hereditary disorder that is the most common colon cancer syndrome in an autosomal dominant form. At first, germline mutations in the APC gene (adenomatous polyposis) were identified as the main genetic factor causing FAP, but during subsequent studies, the human MutY (MYH) gene with an autosom...

Introduction: Familial adenomatous polyposis (FAP) is a rare and hereditary disease in which multiple precancerous polyps develop in the patient's colon. Familial adenomatous polyposis is caused by mutations in the APC gene (5q21). According to new research, in addition to nuclear disorders, mitochondrial functional disorders are also one of the es...

Introduction: Cardiovascular diseases are currently the leading cause of death in the world. Arrhythmias are one of the most common cardiovascular diseases. In arrhythmia, the heartbeat becomes slow, fast, or irregular, which affects the efficiency of the heart, and in this case, the heart may not have enough ability to pump blood. Cardiac arrhythm...

Most studies aiming at unraveling the molecular events associated with cardiac congenital heart disease (CHD) have focused on the effect of mutations occurring in the nuclear genome. In recent years, a significant role has been attributed to mitochondria for correct heart development and maturation of cardiomyocytes. Moreover, numerous heart defect...

Introduction: Abortion is a common complication that refers to the early termination of pregnancy with the death of the fetus before the 20th week of pregnancy. Previous studies show that many genes are involved in this disease, including the CX3CR1 gene, which is one of the inflammatory response genes in the immune system. The pathogenicity of the...

During bone marrow B-cell development, the pre-B-cell receptor is formed by the association of the immunoglobulin heavy chain with a surrogate light chain, which is encoded by the VPREB1, and λ5 genes. It is known that pre-BCR signaling signifies a critical checkpoint at the pre-B-cell stage. Thus, failure pre-BCR signaling is proposed as a critica...

Congenital hypothyroidism (CH) occurs with a relatively alarming prevalence in infants, and if not diagnosed and treated in time, it can have devastating consequences for the development of the nervous system. CH is associated with genetic changes in several genes that encode transcription factors responsible for thyroid development, including muta...

Objective Transcription factor GATA4 has significant roles in embryonic heart development. Mutations of GATA4 appear to be responsible for a wide variety of congenital heart defects (CHD). Despite the high prevalence of GATA4 mutations in CHD phenotypes, extensive studies have not been performed. The 3′-untranslated region (3′-UTR) of the GATA4 gen...

Background: CDKN2A, encoding two important tumor suppressor proteins p16 and p14, is a tumor suppressor gene. Mutations in this gene and subsequently the defect in p16 and p14 proteins lead to the downregulation of RB1/p53 and cancer malignancy. To identify the structural and functional effects of mutations, various powerful bioinformatics tools ar...

Background Familial adenomatous polyposis (FAP) as a colon cancer predisposition syndrome is an autosomal‐dominant inherited condition and is diagnosed by the progress of hundreds or thousands of adenomatous colonic polyps in the colon. This study aims at the nature and effect of Adenomatous Polyposis Coli (APC) gene mutations in FAP tumorigenesis....

Background: Congenital central hypothyroidism (CCH) is a rare autosomal recessive disease caused by mutations in the thyroid-stimulating hormone β subunit (TSHβ) gene. Since patients with CCH do not experience increased serum levels of TSH, the diagnosis is usually delayed, which leads to negative consequences in the neonatal TSH screening. Genetic...

Nuclear genetic mutations have been extensively investigated in solid tumors. However, the role of the mitochondrial genome remains uncertain. Since the metabolism of solid tumors is associated with aerobic glycolysis and high lactate production, tumors may have mitochondrial dysfunctions. Familial adenomatous polyposis (FAP) is a rare form‌ of col...

Introduction: Atherosclerosis is the important cause of most cardiovascular diseases, with high prevalence and mortality. Atherosclerosis is not only a lipid metabolism disorder but also recently is defined as a chronic inflammatory disease. Several studies showed that interleukin-6 (IL-6) is involved in the pathogenesis of atherosclerosis. The aim...

MicroRNAs (miRNAs, miRs) are small endogenous non-coding RNAs that regulate the expression of protein-encoding genes at the post-transcriptional level. Several studies have described the role of miRNAs in T-cell acute lymphoblastic leukemia (T-ALL), including tumor suppressor and oncogenic miRNAs. Down-regulation of miRNA expression is a prominent...

A wide range of genetic and environmental interactions are involved in the development of coronary artery disease (CAD). Considerable evidence suggests that mitochondrial DNA mutations are associated with heart failure. In this work, we examined the possible mutations in hotspot mitochondrial genes and their association with Iranian patients with c...

Introduction: Pregnancy and health is the process in which the egg is fertilized and being able to survive. When pregnancy occurs under some conditions and the fetus is being at risk, it will lead to abortion that occurs involuntarily and spontaneously. Abortions that occur more than two or three times are called recurrent pregnancy loss (RPL). Var...

CITED2 is a cardiac transcription factor that plays a critical role in cardiac development. Gene mutations in CITED2 lead to a series of cardiac malformations and congenital heart defects (CHD). Congenital heart disease generally refers to defects in the heart’s structure or function and often seen in many forms such as ventricular septal defects (...

Background and Objectives: Varicocele is one of the most common causes of male infertility. Varicocele is an abnormal dilatation and tortuosity of veins of the pampiniform plexus, which drain the testis. Studies have shown that elevated level of oxidative stress markers, such as nitric oxide (NO) in the dilated veins of patients with varicocele imp...

Background: Numerous researches have provided great evidence that revealed the relationship between varicocele and sperm DNA damage. Objective: Because of the crucial role of nuclear transition proteins (TPs) in sperm DNA condensation and integrity, this case-control study was designed to study TNP2 gene nucleotide variations in Iranian patients...

Objective Berberis vulgaris contains antioxidants that can inhibit DNA cleavage. The purpose of this study was to evaluate the antioxidant and protective activity of B. vulgaris on DNA cleavage. Materials and Methods In this study, the antioxidant capacity of B. vulgaris was investigated using DPPH and its protective effect was evaluated on pBR322...

Induced pluripotent stem cells (iPSCs) are reprogrammed from somatic cells through numerous transcription factors. Human induced pluripotent stem cell approaches are developing as a hopeful strategy to improve our knowledge of genetic association studies and the underlying molecular mechanisms. Rapid progression in stem cell therapy and cell reprog...

Background: The Angiotensin Converting Enzyme (ACE) Insertion/Deletion and rs-4343 gene polymorphisms could be associated with pathogenesis of essential hypertension and cardiovascular disorders and Coronary Artery Disease (CAD). In the present study, a fast and novel approach of multiplex Tetra-Primer Amplification Refractory Mutation System-PCR...

Non-dystrophic myotonias (NDM) are rare diseases caused by defects in skeletal muscle chloride and sodium ion channels. It is well established that high-energy consuming tissues such as muscular and nervous systems are exclusively dependent on the ATP generation by mitochondria. The mitochondrial dysfunction, which is caused by mitochondrial DNA mu...

Background and objective: Congenital heart disease (CHD) is the most common birth abnormality in the structure or function of the heart that affects approximately 1% of all newborns. Despite its prevalence and clinical importance, the etiology of CHD remains mainly unknown. Somatic and germline mutations in cardiac specific transcription factor gen...

Introduction: Congenital heart diseases (CHDs) are structural cardiovascular malformations that arise from abnormal development of the heart during the prenatal life. Mutations in the TBX5 gene, encoding T-box transcription factor, are a major cause of CHD. To evaluate the TBX5 mutations in hotspot exons in sporadic pediatric patients with CHD phen...

The most common complication of pregnancy is idiopathic recurrent pregnancy loss (RPL). To identify the contribution of gene polymorphisms to this condition, we evaluated the association between RPL and the angiotensinogen (AGT), angiotensin receptor 1 (AGTR1) and Angiotensinogen converting enzyme (ACE). In this case–control study, the frequency of...

Introduction Multiple Sclerosis (MS) is a disease of central nervous system that mainly causes lesions or plaques in the spinal cord and brain. The purpose of this study was to analyze the relation between c.-813C>T (rs2070744) and c.894G>T (rs1799983) polymorphisms of NOS3 gene and MS in Iranian patients. Methods A total of 78 patients with MS an...

Background The embryonic development of the thyroid gland is regulated by the expression of several candidate genes which are related to congenital hypothyroidism. These genes include the numerous critical thyroid transcription factors such as NKX2.1, NKX2.5, FOXE1, and PAX8. The molecular analysis of these loci will be essential to the explanation...

Introduction: The T to C transition at nucleotide 1565 of the human glycoprotein IIIa (ITGB3) gene represents a genetic polymorphism (PlA1/A2) that can influence both platelet activation and aggregation and that has been associated with many types of disease. Here, we present a newly designed multiplex tetra-primer amplification refractory mutation...

Background: Non-dystrophic myotonias are a heterogeneous set of skeletal, muscular channelopathies, which have been associated with point mutations within sodium channel α-subunit (SCN4A) gene. Because exons 22 and 24 of SCN4A gene are recognized as hot spots for this disease, the purpose of the study is to identify mutation in exons 22 and 24 of...

Background: Atherosclerosis is a complex multifocal arterial disease involving interactions between multiple genetic and environmental factors. Objectives: In the present study, we investigated the possible association between NOS3 (rs1799983), MTHFR (rs1801133), APOB (rs5742904) and TNF-α (rs361525) polymorphisms and the risk of coronary athero...

Multiple Sclerosis (MS) is a common disease of the central nervous system. The interaction between inflammatory and neurodegenerative processes typically results in irregular neurological disturbances followed by progressive disability. Mitochondrial dysfunction has been implicated in neurodegenerative disorders. The DNA polymerase-gamma (POLG) gen...

Background: Varicocele is associated with the failure of ipsilateral testicular growth and development, and the symptoms of pain and reduced fertility. The highly condensed structure of the sperm nuclear chromatin is provided by proper expression of Transition Nuclear Protein (TNP) genes, so any dysregulational expression of these genes results in...

Friedreich's ataxia is the most common form of hereditary ataxia with autosomal recessive pattern. More than 96% of patients are homozygous for GAA repeat extension on both alleles in the first intron of FXN gene and the remaining patients have been shown to be heterozygous for a GAA extension in one allele and point mutation in other allele. In th...

Objective(s) : Apolipoprotein E genotype (APOE) polymorphism affects lipid levels and coronary artery disease (CAD) risk. The aim of this study was to study the association of the Apolipoprotein E genotypes with coronary artery disease in the Iranian population. Materials and Methods: The Apolipoprotein E genotype in DNA samples extracted from 66...

Background: Brugada syndrome (BrS) is a rare cardiac arrhythmia characterized by sudden death associated with electrocardiogram patterns characterized by incomplete right bundle-branch block and ST-segment elevations in the anterior precordial leads. This syndrome predominantly is seen in younger males with structurally normal hearts. Mitochondria...

Varicocele is associated with impaired testicular function and male infertility, but the molecular mechanisms by which fertility is affected have not been satisfactorily explained. The aim of our study was to investigate whether or not the polymerase gamma (POLG) polymorphism is associated with Iranian varicocele patients. We determined the POLG CA...

Friedreich's ataxia (FRDA) is a neurodegenerative disorder caused by decreased expression of the mitochondrial protein frataxin. Recently we showed in a clinical pilot study in Friedreich's ataxia patients that recombinant human erythropoietin (rhuEPO) significantly increases frataxin-expression. In this in vitro study, we investigated the role of...

Long QT syndrome (LQTS) is among arrhythmia disorders of the heart that causes sudden cardiac death in young individuals. As yet, most of investigations have focused on nuclear genome for finding genetic defects in this disorder, but some of the cases with LQTS cannot be explained by mutations of identified genes. On the other hand, it has been rep...

Friedreich’s ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by decreased expression of the protein Frataxin. Frataxin deficiency leads to excessive free radical production and dysfunction of chain complexes. Mitochondrial DNA (mtDNA) could be considered a candidate modifier factor for FRDA disease, since mitochondrial oxi...

Friedreich's ataxia (FRDA) is an inherited recessive disorder characterized by progressive neurological disability and heart abnormalities. A deficiency in the protein frataxin causes this disease. Frataxin deficiency leads to progressive iron accumulation in mitochondria, excessive free radical production and dysfunction of respiratory chain compl...

Friedreich’s ataxia (FRDA), an autosomal recessive neurodegenerative disorder, is in most cases due to a homozygous intronic expansion resulting in the loss of function of frataxin. As mitochondrial DNA (mtDNA) copy number has been decreased in FRDA cells and mtDNA polymerase (POLG) is involved in the replication of mtDNA, we searched a trinucleoti...