GENETICS IN THE 3RD MILLENNIUM
Year:2011 | Volume:9 | Issue:3|Papers Count:15

Utilization of fetal hemoglobin inducing drugs is of crucial importance in novel therapeutic approach of b-thalassemia and sickle cell disease. These drugs induce fetal hemoglobin production by several mechanisms such as increasing the proliferation and differentiation of erythroid progenitors. Thalidomide and sodium butyrate are two fetal hemoglobin inducers used as single and combination treatments. This research performed on erythroid progenitors derived from CD133+ cord blood stem cells. Flow cytometry was used for evaluation of the homogeneity of isolated CD133+ cells. Then, the colony formation potential of defined treated groups was evaluated using colony formation assay. Flow cytometry analysis showed the homogeneity of isolated CD133+ cord blood stem cells more than 95%. Also, the results of colony formation assay showed the potential of thalidomide in increasing the hematopoietic and erythroid colony count (1.3- and 1.5- fold increase, respectively) as compared to the control (p<0.05). The results of this study showed that thalidomide has a high potential in colony formation without cytotoxic effects on erythroid progenitors as compared to sodium butyrate and combination treatment (p<0.05).

Muscular dystrophies are often multisystemic disorders with progressive muscle weakness and defects in muscles’ protein. There are nine subtypes of muscular dystrophies such as dystrophinopathies, sarcoglycanopathies and congenital muscular dystrophies. It is necessary to have definite diagnosis of muscular dystrophies by clinical and experimental tools such as CK activity assay, electromyography or ultrasonography, PCR and muscle biopsy in order to have the benefits of genetic counseling, prenatal diagnosis, and possible treatments and also to decrease the prevalence of the disease. So, for the first time in Iran and in order to diagnose and differentiate muscular dystrophies at protein level 72 patients underwent muscle biopsy followed by histopathology and immunohistichemisry assays. In conclusion, 44 patients were identified: 24 patients with dystrophinopathy including 6 duchenne muscular dystrophies and 18 becker muscular dystrophies, 14 patients with limb-girdle muscular dystrophy including 11 sarcoglycanopathies and 3 dysferlinopathies and 6 patients with merosin deficiency (congenital muscular dystrophy). Furthermore, tissue samples of 28 patients which are all positive for the available antibodies were stored for future studies.

Chromosome microarray is being suggested and replacing karyotype as first tier diagnostic test for individuals with unexplained developmental delay/intellectual disability (DD/ID), autism spectrum disorders (ASD), or multiple congenital anomalies (MCA). Chromosome microarray gives a diagnostic yield of 15-20% for genetic testing of individuals with DD/ID, ASD or MCA compared to 3% in karyotype (excluding Down syndrome and other recognizable chromosomal syndromes). We present the results of chromosome microarray performed on 110 individuals with DD/ID, ASD or MCA. From the 110 cases, 23 cases (20.9%) showed copy number variations, of which 13 were deletions, 5 were duplication and 5 were duplication and deletion. The limitations of chromosome microarray are for detection of balanced translocation and low-level mosaicism, but these chromosomal abnormalities are rare causes of abnormal phenotypes in this category of patients.

Iran is the original source and one of the important places for diversity of Astragalus species. Astragalus gossypinus species, which is the producer of tragacanth, belongs to papilionaceae family, is mostly spread in Asia. Alborz and Zagros heights are the most important places where the tragacantha grows in Iran. Astragalus covers around 31.3% area of Isfahan Province. The morphological and ecological aspects of Astragalus gossypinus are well investigated. In the present study, genetic characteristics of Astragalus gossypinus subpopulations are considered for further evaluation. The results of this comparative study can be used in generation and production of high quality tragacanth based on Astragalus places of growth. Thus, Astragalus gossypinus samples were collected from six sites in Isfahan Province. The whole genome was extracted by CTAB method and the extracted DNA quality was examined on electrophorus gel. A part of CNGC4 gene from different samples was amplified for further sequencing. Multi-alignment analysis of the sequences indicated a genetic similarity among Astragalus gossypinus subpopulations. Data indicated that the genotypes of subpopulations were identical. Thus, we concluded that any variation in quantity and quality of produced tragacanth was due to alteration in environment of these subpopulations.

Microarray technology has a wide usage in the fields of genomics and proteomics and enables us to monitor innumerable biological interactions simultaneously. This technology is very efficient and analyzes a lot of data in a short interval. The findings of microarray are then processed analyzed using bioinformatics. The basis of all microarrays is similar: there is a solid surface on which specific ligands are spotted. Then, a biological solution is poured on the surface and based on the binding of the ligand to the specific substance, the results are analyzed.

MicroRNAs (miRNAs) are evolutionary conserved non-coding RNA molecules with approximately 18-25 nucleotids. MicroRNAs regulate gene expression at post-transcriptional level by either inducing mRNA degradation or inhibiting mRNA translation. MicroRNAs have been implicated in the control of physiological and pathological cellular processes. Many miRNAs can act as oncogenes or tumor supressors, therefore, mutations in the open reading frame of these molecules may contribute to cancer. Identification of the miRNAs and their target molecules may open up new avenues for understanding the pathways involved in cancer. This review article will discuss the molecular biogenesis of miRNAs and their synthesis in addition to their function and recognition of their molecular targets. On the other hand, the present article evaluates the recent information about the impact of miRNAs on the diagnosis and treatment of cancer and how these micro molecules may interfere with the biological characteristics of cancer cells.

Aptamers are single – stranded DNA or RNA oligonucleotides with usually 20 – 100 nucleotides and have unique three – dimensional structure that is determined by the nucleotide sequence. This structure affects the binding of aptamer to its targeting molecules. The high efficiency of aptamer technology will likely make them new valuable tools in the diagnosis and treatment of various diseases like neoplasms. In this article, we will review some researches in this regard.

Plants show defensive responses against various pathogens including viruses by activation multiple resistant mechanisms such as hypersensitive response and systemic acquired resistance. Plant resistance involve in recognizing of viruses and signaling after virus recognition. In this regard, plant resistant proteins recognize viral Avr products directly or indirectly. After recognizing viruses by plants, R protein complex function should be changed from recognition to signal transduction. Different molecules including reactive oxygen intermediates, nitric oxide, salicylic acid, jasmonic acid, ethylene, polyamins and MAP kinase cascades play a role in these signaling pathways. It seems that plants develop connection between these pathways to limit viral infections effectively.

Pallister-Killian Syndrome is one of the etiologies of severe intellectual disability with a peculiar face, caused by mosaicism for tetrasomy of chromosome 12p. It is characterized by severe mental retardation, hypotonia, sparse bitemporal hair, sparse eyebrows and eye lashes, a coarse face, hypertelorism, chubby cheeks, cupid bow lips and no speech. In this article, we report a 3-year-old girl with severe mental retardation, no speech and a peculiar face. CGH array documented Pallister-Killian Syndrome.

Peroxisome Proliferator-Activated Receptor g (PPARg) belongs to the nuclear receptor dependent ligand-activated transcription factors that regulates expression of many genes involved in metabolism, cell differentiation, adipogenesis, inflammation and apoptosis. Despite numerous studies which have been published on PPARg activation during ectodermal differentiation, there are a limited number of studies on the role of PPARg in endodermal differentiation. Thus, the aim of this study was to assess the expression of PPARg during in vitro differentiation of mouse embryonic stem cells (mESCs) into definitive endoderm (DE). In this study we demonstrated that an increase of PPARg expression profile occurred upon retinoic acid (RA) treatment in the process of differentiation. This may arise from a possible role of PPARg in the process of endodermal differentiation which should be clarified in further studies.