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Rare Mutations in Evolutionary Dynamics  [PDF]
Anna Lisa Amadori,Antonella Calzolari,Roberto Natalini,Barbara Torti
Quantitative Biology , 2012,
Abstract: In this paper we study the effect of rare mutations, driven by a marked point process, on the evolutionary behavior of a population. We derive a Kolmogorov equation describing the expected values of the different frequencies and prove some rigorous analytical results about their behavior. Finally, in a simple case of two different quasispecies, we are able to prove that the rarity of mutations increases the survival opportunity of the low fitness species.
Detection of Rare and Unknown Mutations in - tathalassemia Traits in Iran
M Habibi Roudknar,H Najmabadi,P Derakhshandeh,DD Farhud
Iranian Journal of Public Health , 2003,
Abstract: Beta-thalassemia, by its high frequency and heterogenecity, constitues a real problem of health in Iran. Aboute 13 beta globin mutations encompass 70-90% of mutations spectrum in Iran, the rest are rare or unknown. In this study six mutations of the codon IVSI-130(G-C), Fr16 (-C), codon35 (-C), fr23/24(-G), codon8 (+G) and codon 20 (GTG-GAG) were recognized and added to spectrom of beta globin mutations in Iran, Using ARMS/PCR and DNA sequencing. Three latter cases are reported for first time.
A rare case of coinheritance of Hemoglobin H disease and sickle cell trait combined with severe iron deficiency  [cached]
Michael Medinger,Elisabeth Saller,Cornelis L. Harteveld,Thomas Lehmann
Hematology Reports , 2011, DOI: 10.4081/hr.2011.e30
Abstract: We present a case of a 40-year-old female from Turkey, who was referred to our outpatient clinic for an undetermined thalassemia and sickle cell trait. At first consultation hemoglobin was decreased (71 g/L) with microcytosis (MCV 55.1 fL), and hypochromia (MCHC 239 g/L). The patient had severe iron deficiency. Brilliant cresyl blue staining showed >50% of the erythrocytes with typical Hemoglobin H (HbH) inclusions. High-performance liquid chromatography (HPLC) revealed normal levels of HbA2 and Hemoglobin F (HbF), and additionally a hemoglobin S (19%). Molecular diagnostics revealed the mutations α2 IVS-I donor site -5nt and a -- MED II deletion in the alpha gene complex and confirmed the heterozygote mutation of the beta-gene at codon 6 (HBB:c.20A>T; HbS). In conclusion, we present an extremely rare combination of HbH disease and sickle cell trait. This combination may explain the mild form of the HbH disease, with moderate anemia, splenomegaly but iron deficiency, rather than iron overload, as usually observed in HbH disease.
Co-Inheritance of Sickle Cell Trait and Thalassemia Mutations in South Central Iran  [PDF]
N Saleh-Gohari,M Mohammadi-Anaie
Iranian Journal of Public Health , 2012,
Abstract: Background: We aimed to determine the incidence of co-inheritance as well as interaction of sickle cell trait (SCT)and αthal/βthal mutations in south and south central of Iran.Method: We employed a PCR and restriction fragment length polymorphism techniques to confirm diagnosis of sickle cell trait. All subjects were screened for any α/β –thalassemia mutations using a gap-polymerase chain reaction and amplification refractory mutations system.Results: Our results showed combination of sickle cell trait and β-globin mutation results in a severe clinical course of similar to sickle cell disease, while coinheritance of α-globin gene defects usually modulates the clinical course. A coexistence of sickle cell trait and α-globin gene mutation was the frequent genotype in overall samples (57. 5%).Conclusion: Sickle cell trait mainly co-inherits with α-globin gene mutation in the south and south central region of Iran. This combination modulates hematological indices and interferes with the SCT diagnosis.
Rare and unexpected beta thalassemic mutations in Qazvin province of Iran
MR Sarookhani, MH Ahmadi
African Journal of Biotechnology , 2010,
Abstract: About 13 beta-globin mutations encompass 70 - 90% of mutation spectrum in Iran. These mutations are called common beta-globin mutations. The rest are rare or unknown mutations. The objective of this study was to identify and describe rare or unknown beta-globin mutations in Qazvin province. EDTAcontaining venous blood samples were collected from 100 patients with transfusion-dependent betathalassemia from the department of pediatrics of Qods hospital of Qazvin. Screening for causal mutations was carried out on DNA isolated from WBCs of the patients by using Amplification Refractory System (ARMS) technique. 14.1% of alleles which were not discovered by ARMS, were uncovered by direct sequencing that include 9 different rare mutations. Thirty-seven combinations of alleles (genotypes) were recognized in all affected patients. The frequency of mutations of nt-30, IVS I-6, Cd5, IVS II-745, 5′ UTR, Cd15, Cd39, IVS I-130, Cd24, Cd74/75, HbS and Hb Monroe were about 1% or less. We have revealed and described the existence of 9 rare mutations from Qazvin, two of which (Cd74/75 and Hb Monroe) are the first reported in Iran.
Inference of dispersion measure from incoherent time-steady sources  [PDF]
Christopher M. Hirata,Matthew McQuinn
Physics , 2013, DOI: 10.1093/mnras/stu509
Abstract: Several recent papers have proposed schemes by which a dispersion measure, and hence electron column, could be obtained from a time-steady, incoherent radio source at a cosmological distance (such as an active galactic nucleus). If correct, this would open a new window on the distribution of intergalactic baryons. These schemes are based on the statistical properties of the received radiation, such as the 2- or 4-point correlation function of the received electric field, and in one case on the quantum nature of the electromagnetic field. We show, on the basis of general principles, that these schemes are not sensitive to dispersion measure (or have an extremely small signal-to-noise ratio), because (i) the classical 2-point correlation function is unaffected by dispersion; (ii) for a source with a large number of incoherently emitting electrons, the central limit theorem obliterates additional information in higher-order functions; and (iii) such an emitter produces a radiation density matrix that is equivalent to a statistical distribution of coherent states, which contains no information that is not already in the statistics of the classical waveforms. Why the proposed observables do not depend on dispersion measure (or have extremely tiny dependences) is discussed in detail.
Germline PTEN mutations are rare and highly penetrant
Cecilie F Rustad, Merete Bj?rnslett, Ketil R Heimdal, Lovise M?hle, Jaran Apold, P?l M?ller
Hereditary Cancer in Clinical Practice , 2006, DOI: 10.1186/1897-4287-4-4-177
Abstract: In 1963 Lloyd and Dennis described a patient named Rachel Cowden who died of bilateral breast cancer in her thirties [1]. Cowden syndrome is now recognized as an autosomal dominant syndrome characterized by multiple hamartomas originating from all three germ-cell layers. Mucocutaneous lesions including trichilemmomas are seen in 90-100% of patients [2]. There is increased risk of early breast cancer from 14 years of age, and lifetime risk is estimated to 25-50% [3-5]. Goitre and thyroid adenomas are frequently seen and the estimated prevalence of thyroid cancer is 3-7% [3,6,7]. We have previously reported endometrial cancer in one Norwegian family with Cowden syndrome [8].In 1995 the International Cowden Syndrome Consortium was formed and a set of clinical diagnostic criteria were suggested; see Table 1[2,9,10]. In 1997 the susceptibility gene for Cowden syndrome was identified on chromosome 10q23.3 and was found to be PTEN [11,12]. Germline mutations are found throughout the PTEN gene, the majority in exons 5, 7 and 8 [2,13]. The frequency of germline PTEN mutations, including mutations in the promoter region, in Cowden syndrome have been reported to approach 85-90% [14]. Genotype/phenotype correlations have been suggested, but have not been confirmed [15-17].Nelen has estimated the incidence to be between 1 per 200,000 and 1 per 250,000 in the Dutch population [16].As for all inherited cancer syndromes, the penetrance of the underlying genetic defects and the full clinical spectrum of their expressions have been difficult to assess without access to genetic testing.Fifty to sixty percent of patients with Bannayan-Riley-Ruvalcaba syndrome (BRRS, MIM 153480) have been shown to have germline mutations in the PTEN gene [14,18]. An association between germline PTEN mutations and Proteus syndrome (MIM 176920) has been disputed [19-22].Our aim was to validate strategies to identify families with PTEN mutations and to estimate prevalences and penetrances of PTEN mutations
Detection of Rare Beta Globin Gene Mutations in Northwestern Iran
MA Hosseinpour Feizi,AA Hosseinpour Feizi,N Pouladi,M Haghi
Journal of Shahid Sadoughi University of Medical Sciences , 2007,
Abstract: Introduction: Recent molecular studies on Iranian β-thalassemia genes revealed the presence of eight common mutations associated with thalassemia. Although these mutations are frequent, there are other rare and unknown mutations that can create large problems in designing preventive programs. We detected and explained the common mutations in north-western Iran previously and detection of the rare and unknown mutations could be useful in diagnosis and design of future preventive programs. Methods: In this study, 5ml peripheral blood from 20 Azari- β-thalassemia patients whose mutation was not revealed in the previous study was collected and DNA extraction was done by isopropanol and proteinase k method. Initially, samples were examined for the rare mutations: Codon6, Codon16, Codon41/42, Codon36/37, -88 and Codon22 by ARMS – PCR techniques and then the unknown cases were directly sequenced. Results: According to our results, Codon15(TGG-TGA), Codon16(-C), Codon36/37(-T), IVSII-848(C-A), IVSII-745(C-G), -28(A-C( and Codon25/26(+T) were recognized and added to the spectrom of beta globin gene mutations in Azerbaijan and Iran. Also, we detected four SNP sites: 5’UTR+20(C-T), Codon2 (CAC-CAT) , IVSII-16(C-G) and IVSII-666(T-C) in β-thalassemia genes. Conclusion: Our results could be useful for developing molecular screening plans and help prenatal diagnosis of beta thalassemia in Azerbaijan , Iran and other neighboring countries.
Why are diploid genomes widespread and dominant mutations rare?  [PDF]
Diana Garncarz,Stanislaw Cebrat,Dietrich Stauffer,Klaus Blindert
Quantitative Biology , 2006,
Abstract: We have used the sexual Penna ageing model to show that the relation between dominance and recessiveness could be a force which optimizes the genome size. While the possibility of complementation of the damaged allele by its functional counterparts (recessiveness) leads to the redundancy of genetic information, the dominant effect of defective genes tends to diminish the number of alleles fulfilling the same function. Playing with the fraction of dominant loci in the genome it is possible to obtain the condition where the diploid state of the genome is optimal. If the status of each bit position as dominant or recessive mutations is changed for each individual randomly and rarely, then after a long time a stationary equilibrium of many recessive and few dominant loci is established in the sexual Penna model. This effect vanishes if the same changing distribution of dominant loci applies to all individuals.
Combination of two rare mutations causes β-thalassaemia in a Bangladeshi patient
Moosa, Mahdi Muhammad;Ayub, Mustak Ibn;Bashar, AMA Emran;Sarwardi, Golam;Khan, Waqar;Khan, Haseena;Yeasmin, Sabina;
Genetics and Molecular Biology , 2011, DOI: 10.1590/S1415-47572011005000026
Abstract: screening of mutations that cause β-thalassaemia in the bangladeshi population led to the identification of a patient with a combination of two rare mutations, hb monroe and hbb: -92c>g.the β-thalassaemia major male individual was transfusion-dependent and had an atypical β-globin gene cluster haplotype. of the two mutations, hb monroe has been characterized in detail. clinical effects of the other mutation, hbb: -92c>g,are unknown so far. bioinformatics analyses were carried out to predict the possible effect of this mutation. these analyses revealed the presence of a putative binding site for egr1, a transcription factor, within the hbb:-92 region. our literature survey suggests a close relationship between different phenotypic manifestations of β-thalassaemia and egr1 expression.
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