In spite of advances in genetic evaluations through genomic information، using epigenetic information is still required. Recent progress in epigenetic indicates that the most environmental factors (maybe all of them) affect animal’s phenotype via epigenetic. Epigenetic includes alterations in chromatin structure and collectively establishes different patterns of gene expression and silencing in genome and is transferred during mitotic and meiotic divisions. In the present study، the mechanisms causing the epigenetic regulations and application of epigenetic in animal breeding are discussed، and new opportunities created by this interesting field have been explained. Three types of epialleles including permanent، temporary and intergenerational، which can be used in epigenetic models have also been proposed. Furthermore، using previous results of other researches we firstly present a model at the molecular level explaining the relationship between epigenetic، genetics and environment in quantitative traits. According to this model، using interaction between epigenetic، genetics and environment can improve estimation of breeding values and reduce their biases.

Plant epigenetic has become one of the key research topics not only as the subject of basic research, but also as a new source of useful traits for plant breeding. Epigenetic regulation is necessary for the production of differentiated cells throughout plant development, as well as maintaining the stability and integrity of the gene expression profiles. Although epigenetic processes are essential for natural growth, they can become misdirected led to abnormal phenotypes and diseases. Epigenetics is the study of heritable phenotype changes that do not involve alterations in the DNA sequence. The microstructure (not code) of DNA itself or the associated chromatin proteins may be modified, causing activation or silencing. This mechanism enables differentiated cells in a multicellular organism to express only the genes which are necessary for their own activity. In this review, our goal is to introduce epigenetics and its different applications in plants, especially in production of transgenic plants, plants tolerate to biotic and abiotic stresses and understanding the mechanisms of gene silencing. Also, in this review, we have referred to the role of transposons in epigenetic, epigenetic engineering methods, epigenetic fingerprinting and ultimately methods for epigenetic data analysis and related databases.

Aim: In this study, we explored the effect of epigenetic modifications on planarian regeneration process by treating with small molecule epigenetic modifiers
Material and Planaria worms were cut into 3 sections including head, trunk, and tail regions and treated with 6 small molecules with epigenetic modification effects. All samples were evaluated morphologically for 20 days to monitor the effects on regeneration process.
Morphological analysis of samples treated with selected six small molecules with different epigenetic modification functions revealed that treating with two of them including Sodium butyrate and Valporic acid will result in delayed head, trunk, and tail fragments regeneration, and delayed eye formation in trunk and tail fragments, respectively. In addition, samples treated with other four small molecules including BIX01294, RG108, SAHA, and Tranylcypromine with other epigenetic modification functions, regenerated normally.
These results indicating that different epigenetic levels and activity of histone deacetylases play a key role in planarian regeneration and inhibition of histone deacetylases activity will result in abnormal regeneration. However, further work is needed to determine the exact mechanism of histone deacetylases activity effect on planarian regeneration process. Finally, we hope to understand more about the underlying mechanism of planarian and vertebrate’s regeneration inhibition and activation using these findings.

Diabetic vascular complications (DVC) influence several vital organ systems including cardiovascular, renal, ocular and nervous systems making it a major public health problem. Although extensive researches were performed in this field, the exact mechanisms responsible for these organ damages in diabetes remain obscure. Several metabolic disturbances have been involved in its complication and change in genes associated with these pathways occurred. Gene expression to produce a biologically active protein can be controlled by transcriptional and translational alteration on the head of genes without change in nucleotide composition. These epigenetic adjustments are steady, but possibly reversible and can be transmitted to future generation. Gene expression can be regulated by three epigenetic mechanisms including DNA methylation, histone modifications and noncoding microRNAs (miRNAs) activity. Epigenetic studies must be directed to better realize the role of epigenetic changes to the etiology of DVC and knowledge of epigenetic would play a pivotal role in the application of individualized medicine. Application and development of high technology sequencing combined with more sensitive and advanced methodologies for epigenome studying help to determine specific epigenetic events that stimulate gene responses in patients with diabetes mellitus.

Epigenetic mechanisms attribute to the resistance and virulence of Acinetobacter baumannii sparking a renewed area of research. Unveiling the targets pertained to the epigenetic modulation in the bacterium would aid in the curbing its complications in various recalcitrant infections. This review thus throws light on the various epigenetic mechanisms exhibited by A. bauamnnii, urging the need to implement epigenetic based novel strategies in precision medicine.

Recent studies have indicated that epigenetic alterations are critical for normal function and development of spermatozoa during the fertilization process. This review will focus on the latest advances in epigenome profiling of the chromatin modifications during sperm development, as well as the potential roles of epigenetic mechanisms in the context of male infertility. In this review, all data were collected from published studies that considered the effect of epigenetic abnormalities on human spermatogenesis, sperm parameters quality, fertilization process, embryo development and live births. The database PubMed was searched for all experimental and clinical studies using the Keywords “epigenetic modifications”, “male infertility”, “spermatogenesis”, “embryo development” and “reproductive function”. Post-translational modifications of histone, DNA methylations and chromatin remodeling are among the most common forms of epigenetic modifications that regulate all stages of spermatogenesis and fertilization process. Incorrect epigenetic modifications of certain genes involved in the spermatogenesis and sperm maturation may be a main reason of male reproductive disorder and infertility. Most importantly, abnormal patterns of epigenetic modifications or transgenerational phenotypes and miRNAs expression may be transmitted from one generation to the next through assisted reproductive techniques (ART) and cause an increased risk of birth defects, infertility and congenital anomalies in children. Epigenetic modifications must be considered as a one of the main factors of unexplained male infertility etiology. Due to high risk of transmitting incorrect primary imprints to offspring, there is a need for more research into epigenetic alterations in couples who benefit of ART support.

With 1 million new cases causing 375000 deaths worldwide per year, breast cancer is the leading cause of cancer death in women in both developing and developed countries. Recent findings indicate epigenetic modifications as key factors in breast carcinogenesis. Epigenetic refers to the cellular information of transcription memory which is transmitted through cell divisions but is not sequence based. Epigenetic is the connecting circle of the genotype and the environment. Which connect the inheritable gene transcription pattern and phenotype of a cell. DNA promoter methylation and chromatin remodeling are two main mechanisms of epigenetic modifications which are emerging as targets for breast cancer detection, prognosis and treatment. Because of their potential for reversal, epigenetic alterations are considered to be promising in caner treatment and epidrug production. Therapeutics that target methylation and histone modifications in breast cancer already exist. Advances in epidrugs are likely to play important role in future of cancer treatment.

Epigenetic changes are regulators of gene expression in diverse biological phenomena such as embryonic development, genetic diseases and cancer. Polycomb proteins are a group of epigenetic key players proved to be involved in chromatin structural changes and gene regulation through histon posttranslational modifications. SUZ12 is an important member of polycomb complex in human and has been considered as a biomarker of chromatin epigenetic changes in the cell. SUZ12 down regulation has resulted in activation of progenitor cells and hematopoitic stem cells. Here, SUZ12 gene expression pattern was studied aiming at the relationship of a possible epigenetic modifications and CML in human. First, CML patient blood samples were tested for the occurrence of ABL-BCR translocation through Multiplex-PCR. Then, SUZ12 expression pattern was analyzed through Semi-quantitative RT-PCR in these patients. SUZ12 expression level showed significant reduction in CML patient comparing to the control group. This result is in agreement with the notion that cancer and epigenetic changes are linked and also CML may originate from higher activity of hematopoitic stem cells.

The pathogenesis of systemic lupus erythematosus (SLE) is influenced by both genetic factors and epigenetic modifications; the latter is a result of exposure to various environmental factors. Epigenetic modifications affect gene expression and alter cellular functions without modifying the genomic sequences. CpG-DNA methylation, histone modifications, and miRNAs are the main epigenetic factors of gene regulation. In SLE, global and gene-specific DNA methylation changes have been demonstrated to occur in CD4 T-cells. Moreover, histone acetylation and deacetylation inhibitors reverse the expression of multiple genes involved in SLE, indicating histone modification in SLE. Autoreactive T-cells and B-cells have been shown to alter the patterns of epigenetic changes in SLE patients. Understanding the molecular mechanisms involved in the pathogenesis of SLE is critical for the introduction of effective, target-directed and tolerated therapies. In this review, we summarize the recent findings that highlight the importance of epigenetic modifications and their mechanisms in SLE.

Many neurological and psychiatric disorders are not due to mutations in a specific gene; rather, they are attributed to dysregulation of genes’ functions and signals that control their expression. Complex 'epigenetic' mechanisms regulate various gene activities with long-lasting effects within mature neurons and other cells of brain tissue. The present study reviewed related investigations up to 2021 by searching keywords including epigenetics, DNA methylation, microRNA, RNA editing as well as psychiatric disorders, schizophrenia, autism and bipolar disorder in PubMed database. Among collected articles, the most relevant research articles related to the topic of this article were selected and reviewed. Currently, at least four epigenetic mechanisms are known, that through altering DNA, RNA or histone codes, regulate genes’ expression levels. Meanwhile, these epigenetic mechanisms themselves are under the influence of internal and environmental factors and may be dysfunctional secondary to malnutrition, contaminants, toxins, drugs, substances, infections, etc. Many studies have shown that various epigenetic aberrations are involved in the expression of genes involved in psychiatric disorders, such as schizophrenia, autism, and bipolar disorder. A comprehensive investigation on epigenetic alterations and the environmental factors that mediate these alterations can help to improve preventive and therapeutic strategies in neuropsychiatric diseases.