Hemoglobin Loci Research Articles

HAEMAGLOBIN TYPES IN SHEEP IN OF SEMI-ARID ZONE OF NORTH EASTERN NIGERIA

Genotyping is not a test to diagnose a disease, but rather a test looking for certain information encoded on the prion protein (PrP) gene. This encoded information helps determine the susceptibility of sampled sheep to developing clinical disease from a disease should the animal be exposed. Therefore, haemaglobin types in sheep in the semi-arid zone of North Eastern Nigeria was determined at haemoglobin (Hb) locus level. One hundred and sixty-eight (168) animals were used for the study. Blood samples comprising 56 each of Yankasa, Balami and Uda breeds were collected from households, sheep and goats’ markets and abattoir. The blood samples were analysed for haemaglobin types. Blood samples (5 mL per animal) were obtained from the jugular vein using a 10 mL syringe attached to 21gauge x ½ inch needle. The blood samples collected was then placed in tubes coated with ethylene-diamine tetra-acetic acid (EDTA) as anticoagulant. The samples were adequately labeled and taken to Federal Teaching Hospital Gombe haematology’s laboratory for analysis. Haemoglobin type was identified using cellulose acetate paper electrophoresis. Genotypic frequencies were estimated, and sheep showed only HbAA genotype. Genotypic frequencies were similar in both sexes of sheep implying that there was no effect in sex on Hb frequency. It is therefore concluded that there were no polymorphisms at Hb locus since only the Hb AA was exhibited.

Asxl1-mutant Dominant Clones Have an Erythropoietic Lineage Deficiency through a Disturbed Epigenetic Landscape

Two hematologic features of red blood cells (RBCs) rank among the top three high risk factors associated with increased risk of malignant progression from clonal hematopoiesis (CH). These risk factors are macrocytosis as measured by elevated mean corpuscular volume (MCV) of 100 fL or greater and red cell distribution width (RDW) of 15% or greater. It is not known how these changes in RBC parameters are related to the leukemic transformation. Without major disturbance in the quantitative output of RBCs, these changes may reflect clone specific changes in erythropoiesis that are averaged in such measurements. We used an in vivo model of CH in zebrafish to study epigenetic and transcriptional changes in mutant clones, focusing on the erythropoietic program. In this model, mosaic somatic mutations in exon 12 of asxl1 with CRISPR-Cas9 mutagenesis are combined with color labeling of hematopoietic stem and progenitor cell (HSPC) clones. These mosaic asxl1 mutants exhibit an expansion of single-colored mutant clones to greater than 30% of hematopoietic output. No significant hematopoietic disturbance has been noted in these mutants by flow cytometric and morphologic analysis. To study clone specific effects of this epigenetic factor mutation, we sorted HSPCs from the dominant asxl1-mutant clone and compared it to HSPCs from control animals using transposase-accessible chromatin with sequencing (ATAC-seq) assay. Among over 22,000 peaks, we identified 998 (4.5%) that increased and 938 (4.2%) that decreased by 2-fold in asxl1-mutant clones compared to controls. Of the upregulated peaks, 73% were distal elements (+/- 100kb from transcriptional start sites, TSS) and 27% were proximal or promoter peaks (-2kb to +500bp from TSS), while in decreased peaks 67% were in distal elements and 33% in the proximal/promoter region. Pathway analysis of assigned genes related to decreased peaks identified a striking loss of the erythropoietic program and the heme biosynthesis process. HOMER analysis of sequences within the decreased peaks showed significant association with GATA ( q-value <0.001) and TRPS1 ( q-value <0.001) motifs. This was confirmed by individual assessment of gene loci for lineage-specifying transcriptional factors, such as tal1 and gata1a and genes in erythropoiesis, including alas2, cahz, tmod4 and the hemoglobin locus with known enhancers in nprl3 gene . Using an independently generated mutant zebrafish cohort, we performed bulk RNA-sequencing on sorted dominant clone and control HSPCs. Downregulated genes were consistent with a loss of erythroid differentiation program, with up to 16-fold downregulation of hbba1, hbaa1, alas2 and cahz although less pronounced or no significant changes were noted in erythroid transcription factors ( tal1, gata1a, lmo2) . Our data show that asxl1-mutant clones have an erythropoietic lineage defect with reduced epigenetic accessibility at lineage-specific loci with selective changes in gene expression. This ineffective erythropoiesis characterized by large MCV in mutant RBCs would increase the RDW due to the mixed contribution from mutant and wildtype clones in the peripheral blood. Our findings offer a biologic basis of the strong clinical association of abnormal RBC characteristics with higher risk CH for malignant transformation.

Using DNA testing for the precise, definite, and low-cost diagnosis of sickle cell disease and other Haemoglobinopathies: findings from Tanzania

BackgroundSickle cell disease (SCD) is an important cause of under-five mortality. Tanzania is the 5th country in the world with the highest births prevalence of SCD individuals. Significant advances in the neonatal diagnosis of SCD using rapid point-of-care testing have been made. However genetic confirmation is still required for positive cases, in uncertain cases, in multiply transfused patients, to resolve compound heterozygosity (Hb S/ β0 Thal or Hb S/ β+ thal) not uncommon in the coastal regions of East Africa and increasingly also for pre-marital counselling and potentially for future curative approaches such as gene therapy. The currently available DNA tests are prohibitively expensive. Here, we describe an easy-to-use, affordable and accurate β-globin sequencing approach that can be easily integrated within existing NBS for SCD and other haemoglobinopathies especially in Low- and Middle-income Countries.AimTo evaluate an affordable DNA technology for the diagnosis of Sickle cell disease and other haemoglobinopathies in a resource-limited setting.MethodsLaboratory-based validation study was conducted by Muhimbili University of Health and Allied Sciences and the University of Oxford involving sequencing of the entire β -haemoglobin locus using the Oxford Nanopore MinION platform. A total number of 36 Dried blood spots and whole blood samples were subjected to conventional protein-based methods (isoelectric focusing, HPLC), and/or sequenced by the Sanger method as comparators.ResultsSequencing results for SCD using the MinION were 100% concordant with those from the Sanger method. In addition, the long-read DNA sequencing method enabled the resolution of cases with unusual phenotypes which make up 1% of all children in Tanzania. The cost is £11/ sample for consumables, which is cheaper compared to other sequencing platforms.ConclusionsThis is the first report of a comprehensive single DNA assay as a definitive diagnostic test for SCD and other haemoglobinopathies. The test is fast, precise, accurate and affordable.

Manipulation of Developmental Gamma-Globin Gene Expression: an Approach for Healing Hemoglobinopathies.

β-Hemoglobinopathies are the most common monogenic disorders, and a century of research has provided us with a better understanding of the attributes of these diseases. Allogenic stem cell transplantation was the only potentially curative option available for these diseases until the discovery of gene therapy. The findings on the protective nature of fetal hemoglobin in sickle cell disease (SCD) and thalassemia patients carrying hereditary persistence of fetal hemoglobin (HPFH) mutations has given us the best evidence that the cure for β-hemoglobinopathies remains hidden in the hemoglobin locus. The detailed understanding of the developmental gene regulation of gamma-globin (γ-globin) and the emergence of gene manipulation strategies offer us the opportunity for developing a γ-globin gene-modified autologous stem cell transplantation therapy. In this review, we summarize different therapeutic strategies that reactivate fetal hemoglobin for the gene therapy of β-hemoglobinopathies.

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Artificial regulation and management of the numerical sex ratio of farm animals and poultry is one of the important prerequisites for intensive livestock management. The article considers the genetic characteristics of male turkeys produced via parthenogenesis and fertilized eggs according to blood serum transferrin (Tf), ceruloplasmin (Cp) and hemoglobin (Hb) loci. The findings of genetic and mathematical analyses conducted throughout experimental investigations can be used as genetic markers when implementing selection activities in the mentioned branch.

Features of the genetic structure of the Simmental breed cattle

Breeds of farm animals are characterized by the presence of their genetic structure, in particular, the distribution of allelic and genotypic frequencies by individual genetic and biochemical systems. The purpose of our search was to study the genetic frequencies of polymorphic loci of transferrin (TF), amylase (AM), ceruloplasmin (CR), hemoglobin (HB) and purine nucleoside phosphorylase (PN) in Simmental cattle and related breeds (Gray Ukrainian and Charolais), as well as to determine the degree of similarity between the expected loci and actual genotypes. As a result of research it was established that the genetic structure of the studied polymorphic loci of the Simmental breed was closer in animals of the Gray Ukrainian breed. In particular, at the locus of transferrin in individuals of the Gray Ukrainian breed there are alleles TF A, TF D1, TF D2 and TF E, whose genetic frequency was in the range of 0.051–0.603. The frequency of the Tf A allele in all studied breeds of cattle had a slight intergroup fluctuations (0.235–0.244), indicating their genetic similarity to this allele. At the locus of transferrin allele Tf D1 of the breed Ukrainian and Charolais were characterized by a lower frequency, however, according to the Tf D2 allele (frequency 0.603 in both breeds), they outperformed the Simmental breed by 11.7 %. The amylase locus in the studied breeds occurs with the alleles AM B and AM C, and with the allele AM A – is absent. The frequency of the AM B allele was highest in animals of the Gray Ukrainian breed, and in the AM C allele in the Charolais breed. It should be noted the high frequency of the AM B allele (0.910) in the Gray Ukrainian breed, which is due to the large number of BB homozygotes. Among the ceruloplasmin locus, the CP A allele had the highest frequency, and the CP B allele had a slightly lower frequency. In the hemoglobin locus, the frequency of HB A allele expression was the highest compared to other polymorphic systems and was in the range of 0.905–1.000. As for the HB B allele, on the contrary, the frequency of its appearance was much lower: in Simmental animals it was 0.095, in the Charolais breed it was 0.059, and in the Gray Ukrainian breed this allele was not observed. Among the alleles of purine nucleoside phosphoryls, the PN L allele was noted with a high frequency (0.697–0.846). The study of genotypes of genetic and biochemical systems of Simmental breed by loci TF, AM, SR, HB and PN shows that the locus TF, which is represented by the largest number of genotypes (10), was marked by a high degree of similarity between expected and actual genotypes with a significant difference (exception – genotype TF EE). The largest number of animals at this locus had the genotypes TF AD2, TF D1 D2 and TF D2 D2 (8 heads in each group), and the smallest – with genotypes TF AA, TF D1 D1, TF D1 E and TF D2 E (1–2 heads each). With the expected genotypes TF AF and TF EE, their real number was not detected, which indicates high heterozygosity. Amylase polymorphism is appeqred only by alleles AM B and AM C. Homozygous for allele B recorded a slightly larger number – in 23 individuals, while homozygous for allele C – only in 3 individuals, which coincides with the expected data in accordance with 21.690 and 1.690. The ceruloplasmin locus is marked by a slightly higher frequency of allele A, due to homo- (CP AA) and heterozygotes (CP AB), which appeared in 15 animals in both groups. Hemoglobin in the Simmental breed, as in most breeds of cattle, is represented mainly by allele A, and homozygotes of the BB allele are absent. Allele B is appeared in small quantities in a heterozygous state – in 4 individuals. The РN locus is appeared by two alleles (L and H), and there are no heterozygotes on the electrophoresis foregrams. There was a high frequency of the L allele of the PN locus, which is characteristic of breeds of the dairy direction of productivity. The PN H allele, which is characterized by high activity, is somewhat less common in Simmentals (only in 6 individuals). Thus, the study of genetic frequencies of the Simmental breed is necessary for the identification and early determination of the level of productivity of animals. Genetic frequencies of polymorphic loci are necessary for selection work with the breed, and can also be used in the breeding process to accelerate the rate of the breeding process. Searches of the genetic structure of the complex of genetic and biochemical systems are necessary for the research and preservation of the gene fund of local and endangered breeds of cattle.

English

This study was carried out to investigate the haemoglobin genetic types and their association with qualitative traits in West African Dwarf (WAD) sheep. The Modified Stratified Sampling Technique (MSST) was used to select the sampling sites within the selected state and animal samples within the sampling sites. A total of 280 adult sheep comprising 140 rams and 140 ewes aged 4 years were used for the study. Data were collected on Mendelian traits such as the horn status, wattle status and hair length on sex basis. Blood samples were collected from the animals for haemoglobin genetic types’ determination. The results showed that in ewes, the f(HbAA), f(HbAB) and f(HbBB) were 0.36, 0.28 and 0.36, respectively and the f(HbA) and f(HbB) was 0.50 in both alleles.  In rams, the f(HbAA), f(HbAB) and f(HbBB) were 0.68, 0.14 and 0.18, respectively and the f(HbA) and f(HbB) were 0.75 and 0.25, respectively. In the pooled data, f(HbAA), f(HbAB) and f(HbBB) were 0.68, 0.14 and 0.18, respectively and the f(HbA) and f(HbB) were 0.625 and 0.375, respectively.  The estimated heterozygosity was 0.47 and the estimated local inbreeding coefficient was 0.054. The hair length indicated sexual dimorphism with 12.79 to 12.98 cm in rams and 4.79 to 4.98 cm in ewes but was not dependent on the heamoglobin genetic types. The result shows that the status of wattles is not influenced by sex. The WAD sheep used had three haemoglobin genotypes under the control of two alleles at the haemoglobin locus. Key words: Ewe, haemoglobin genetic type, inbreeding coefficient, Mendelian traits, ram. &nbsp

An evolutionarily ancient mechanism for regulation of hemoglobin expression in vertebrate red cells

AbstractThe oxygen transport function of hemoglobin (HB) is thought to have arisen ∼500 million years ago, roughly coinciding with the divergence between jawless (Agnatha) and jawed (Gnathostomata) vertebrates. Intriguingly, extant HBs of jawless and jawed vertebrates were shown to have evolved twice, and independently, from different ancestral globin proteins. This raises the question of whether erythroid-specific expression of HB also evolved twice independently. In all jawed vertebrates studied to date, one of the HB gene clusters is linked to the widely expressed NPRL3 gene. Here we show that the nprl3-linked hb locus of a jawless vertebrate, the river lamprey (Lampetra fluviatilis), shares a range of structural and functional properties with the equivalent jawed vertebrate HB locus. Functional analysis demonstrates that an erythroid-specific enhancer is located in intron 7 of lamprey nprl3, which corresponds to the NPRL3 intron 7 MCS-R1 enhancer of jawed vertebrates. Collectively, our findings signify the presence of an nprl3-linked multiglobin gene locus, which contains a remote enhancer that drives globin expression in erythroid cells, before the divergence of jawless and jawed vertebrates. Different globin genes from this ancestral cluster evolved in the current NPRL3-linked HB genes in jawless and jawed vertebrates. This provides an explanation of the enigma of how, in different species, globin genes linked to the same adjacent gene could undergo convergent evolution.

Studies of Genetic Distance, Gene and Genotypic Frequencies of Hemoglobin Types of West African Dwarf and Yankassa Sheep

Hemoglobin (Hb) alleles, genotype and their frequencies were studied in 50 West African Dwarf (WAD) and 50 Yankasa sheep. Blood samples were collected from the animals and analysed, hemoglobin (Hb) type were determined by cellulose acetate electrophoresis. The resultant data were subjected to statistical analyses. The gene frequencies estimated in each allele of the population and were tested using Hardy-Weinberg equilibrium. The genetic distance was thereafter estimated according to Bodmer and Cavalli-Sforza method. The frequencies of Hb(A) and Hb(B) in WAD sheep were 0.35 and 0.65 and genotype frequencies were HbAA (0.34), HbAB (0.00) and HbBB (0.66). The corresponding values in Yankassa sheep were 0.75 and 0.25, 0.70, 0.10 and 0.20, respectively. The distribution of the haemoglobin genotypes was tested using Chi-square analysis. The genetic distance at the haemoglobin locus between WAD and Yankassa sheep was estimated and was found to be 0.16, which shows that within the limit of these small populations sampled, there is a similarity of alleles at the locus. Sampling larger number animals in different breeds of sheep will allow for a better genetic studies and marker-assisted selections in sheep improvement programs. Keywords: Genetic Distance, hemoglobin, Sheep, WAD, Yankassa.

Studies on the Productive Traits and Relationship between Breeds of Cattle (Friesian Bunaji Cross, Bunaji and Sokoto Gudali) Using Blood Biochemical Polymorphism

We studied the blood haemoglobin polymorphism and activity in relation to body morphology and milk traits in Nigerian indigenous breeds of cattle. A total of 150 animals, 50 per breed of the Bunaji, Friesian X Bunaji and Gudali were used to study the relationship between breeds. Variables measured were BW: Body weight (Kg); BL: Body Length (Cm); HW: Height at withers (cm); CW: Chest width (cm); HG: Heart Girth (cm); Rumwi: Rump width (cm); TL: Teat Length (cm); RUH: Rear Udder Height (cm); UC: Udder Circumference (cm); TY: Total Yield (Litres); ADY: Average Daily Yield (Litres/day) and LL: Lactation Length (days) and blood protein polymorphism of the Haemoglobin. Observed results showed overall frequencies of 0.62 (HbA) and 0.48 (HbB). Higher frequencies of the A allele (0.52, 0.54 and 0.68) were obtained respectively for the Bunaji, Friesian X Bunaji and Gudali cattle in the Haemoglobin locus. Study of blood protein polymorphism and productivity indicated significant (p<0.05) influence of the haemoglobin. There is a need for a genetic study using other proteins and at DNA level to compliment the results arisen from morphometric differentiation of the two most populous Nigerian breeds of cattle in the NAPRI herd.

Influence of ecological and geographical features of breeding brown Carpathian rocks on its genetic structure

Studying the genetic structure of cattle makes it possible to characterize it by molecular genetic markers, which in the future enable effective breeding work with animals breed to achieve the desired characteristics. Lately is becoming more apparent the need to preserve genetic diversity namely due to the peculiarities of breeding in different ecological and geographical regions. Therefore, we conducted an investigation of the genetic structure of animals of pure-bred Brown Carpathian (BC), Schwyz (S) breeds, their mixtures of the first (F1) generation (1/2BС+1/2S), Brown Carpathian with a share of hereditary breed of Schwyz breed up to 50 and more than 50%, as well as Brown Carpathian, raised in flat and mountain farms. Genetic structure was evaluated by genetically determined polymorphism of groups of genetic-biochemical systems. Of the 14 investigated loci that encode proteins and blood enzymes, polymorphism was identified in five loci, namely: transferrin (Tf), ceruloplasmin (Cr), amylase-1 (Am-1), hemoglobin (Hb), and purine nucleoside phosphorylase (NP). As a result of population-genetic analysis of polymorphic loci of proteins and enzymes of blood in animals of Brown Carpathian breed the following data were obtained:the highest level of heterozygosity (H) was found at the transferrin locus – 95%, the lowest – at the hemoglobin locus – 9.5%.The heterozygosity at the ceruloplasmin locus was 68%. Evaluation of heterozygosity at the purinnucleoside phosphorylase locus was not possible because part of the animals with the NP-H (high activity) phenotype could carry a low activity variant in the heterozygous state. For all polymorphic systems in the Brown Carpathian breed genotype frequency distribution was in a balanced state according to Hardy-Weinberg law, except for the transferrin locus,where a statistically significant deficiency of homozygotes (P > 0.95) in the most common allelic variants is detected. Analysis of the dendrogram showed that groups of animals of Brown Carpathian breed with different proportion of hereditary Schwyz form one cluster that is clearly differentiated from purebred schwyzes. First-generation domestic animals (F1), by genetic structure, are significantly closer to the maternal Brown Carpathian breed than to the Schwyz one. Thus, the data obtained indicate that the specific characteristic of Brown Carpathian breed may be a relatively increased breeding value of a number of allelic interlocal associations, in which the loci of the genetic-biochemical systems are involved in one way or another. Genetic analysis of these systems showed the presence in the breed of its specific features, which are specific to it.

Assessment of Genetic Diversity at the Heamoglobin Locus in Selected West African Dwarf Goat Populations in Nigeria

Blood samples were collected from 40 (forty) goats in Kwande Local Government Area, of Benue State, Nigeria. Blood samples collected were subjected to electrophoresis to study haemoglobin polymorphism and its distribution in West African Dwarf goat populations in Kwande. Data on Haemoglobin genotypes were subjected to sample variance (S2) population genetics simulation software for the analysis. Three heamoglobin genotypes (HbAA, HbAB and HbBB) were observed in the West African dwarf goat populations. The haemoglobin gynotypes (HbAA, HbAB and HbBB) were controlled by two co-dominant haemoglobin alleles HbA and HbB. The genotypic frequencies were 0.24, 0.57 and 0.19 for HbAA, HbAB and HbBB respectively. Genotypic frequencies at the haemoglobin locus in West African Dwarf goat were in hardy-weinberg equilibrium. The gene frequencies of HbA and HbB observed were 0.52 and 0.48 respectively with HbA being the most frequent. The low allelic variation may have occur when populations are separated but only for a short time, that the processes of genetic drift and mutation that leads to differentiations of allelic frequencies at selected loci are yet to occur. As the amount of time in which two isolated populations increases, the differences in allelic frequencies will also increase until each population is completely fixed for a number of alleles. These factors may have accounted for the low variation in the heamoglobin allelic frequencies observed in this study. There was also gene-controlled diversity at the haemoglobin locus in the WAD goat populations with heterozygosity (He) value of 0.49, which indicated a moderate level of genetic diversity at the haemoglobin locus in WAD goat populations in Kwande Local Government Area of Benue State, Nigeria.

Preliminary Assessment of Within-Ecotype Genetic Diversity at the Haemoglobin Locus in the Tiv Local Chickens in Makurdi, Nigeria

This experiment was designed to assess within-ecotype genetic diversity at the haemoglobin (Hb) locus in the Tiv local chickens of Nigeria in Makurdi. Eighty-two (82) blood samples were collected from each bird using needles and vials (SARSTEDT Monovette®). Haemoglobin genotypes were determined using cellulose acetate electrophoresis. Data were analyzed using Population Genetics Simulation (PopGen.S2) software. The result revealed three haemoglobin genotypes (HbAA, HbAB and HbBB) controlled by two co-dominant haemoglobin alleles HbA and HbB in the Tiv local chicken population in Makurdi. Genotype frequencies of HbAA, HbAB and HbBB were 0.44, 0.32 and 0.24, respectively, in the entire chicken population. The gene frequencies of HbA and HbB observed in this study were 0.60 and 0.40, respectively in the entire population. There was moderate heterozygosity (0.48) at the haemoglobin locus in the local chicken population in Makurdi, which is an advantage to the local chicken population.

Hemoglobin E in Northeast India: A review on its origin, distribution, migration and health implication

A systematic review of the studies on hemoglobin E in Northeast India has been carried out to understand the magnitude of research undertaken on this aspect during the last seven decades. Owing to the high prevalence of hemoglobin E in this part of India different authors have studied this hemoglobin from different perspectives and found conflicting results. However a systematic review of such studies is lacking from a holistic point of view. Most of the epidemiological, in vitro as well as in vivo studies show signatures of selection with this hemoglobin locus. However, how this polymorphism is maintained at different rates at different geographical region is still a matter of contention. This review will fill the gap from all perspectives starting from the frequency distribution of hemoglobin E and its spread in different parts of Northeast India, its relationship with malaria hypothesis, the population migration, population affinity and most importantly the health implication arising out of it. A probable origin of hemoglobin E among an Austroasiatic population of Northeast India has been postulated with the help of advance molecular anthropological knowledge like the deep rooted markers of mt DNA and Y-chromosome haplotypes.

An ASGCT Perspective on the National Academies Genome Editing Summit.

The armamentarium of modern genetics and gene therapy has recently expanded with the rapid development of the tools of “genome editing,” including zinc-finger nucleases, TALENs, and CRISPR/Cas9 techniques that allow exquisitely targeted sequence modifications. An alluring application of such technology is somatic cell genome editing for the prevention and therapy of genetic disease. Most scientific, ethics, and policy agencies support somatic cell applications of genome editing; the gene therapy community has understandably taken deep interest because we represent the major biomedical conduit through which the technology will eventually be translated to clinical application.

658. Increasing Fetal Hemoglobin Expression With TALEN Induced Small Deletions in Peripheral Blood Stem Cells

Hemoglobinopathies are common and morbid inherited conditions caused by mutations in hemoglobin genes that generate pathologic globin molecules or reduced expression of wild type hemoglobin. A subset of individuals with hemoglobinopathy-associated beta globin mutations have a mild clinical phenotype and are found to carry additional disease modifying mutations including small deletions or point mutations that induce fetal hemoglobin expression. This condition is referred to as hereditary persistence of fetal hemoglobin. Recent progress in the arenas of gene editing and hematopoietic stem cell (HSC) expansion has raised the possibility of treating hemoglobinopathies through direct modification of genes in HSCs to increase the expression of fetal hemoglobin in the erythroid lineage. To date, most attempts to induce fetal hemoglobin have targeted the expression of transcription factors implicated in regulation of fetal hemoglobin production, such as Bcl11a, an approach which could lead to unintended and potentially deleterious effects on cellular phenotype. Here, we are evaluating the application of mRNA transfection of TALENs to directly modify transcription factor binding sites within the hemoglobin locus in HSCs to achieve efficient, stable expression of fetal hemoglobin. We have designed TALENs to induce small deletions in the beta hemoglobin promoter at the binding site of KLF1, postulated to play a role in localizing the active chromatin hub to and preferentially expressing adult beta hemoglobin, as well as other globin locus target regions implicated in the regulation of fetal hemoglobin production. By combining TALEN-mediated gene modification with novel HSC expansion approaches involving the recently described small molecule UM729, we hope to realize both efficient HSC modification and expansion with a sufficient level of fetal hemoglobin production in erythrocytes to achieve a functional cure for a wide range of beta hemoglobinopathies.

Investigation of haemoglobin polymorphism in Ogaden cattle

Background and Aim: The Ogaden cattle is one among the tropical cattle breeds (Bos indicus) widely distributed in eastern and south eastern part of Ethiopia. The breed has been evolved in arid and semi arid agro-ecological setup, but later on distributed and adapted to the wide agro-ecological zones. Because of its multi-purpose role, the Ogaden cattle have been used for milk, beef, and income generation. Information on the inherent genetic diversity is important in the design of breeding improvement programmes, making rational decisions on sustainable utilization and conservation of Animal Genetic Resources. Limited information is available about genetic variation of Ogaden breed at molecular level. The present investigation was aimed to study the biochemical polymorphism at the Hemoglobin (Hb) locus. Materials and Methods: Blood samples collected from 105 Ogaden cattle maintained at Haramaya beef farm by jugular vein puncture were subjected to agarose gel electrophoresis [pH range 8.4-8.5] to study the polymorphic activities of haemoglobin. Results: Three types of phenotypes were detected i.e. a slow moving (AA) band, fast moving (BB) band and a combination of slow + fast moving bands (AB). The frequency of the fast moving band was less [13 (12.3%)] than the slow moving band [57 A (54.2%)]. Both slow & fast moving phenotype was observed in 35 (33.3%) animals. The gene frequency of HB allele was B 0.709 and that of HB allele 0.291. 2 Conclusion: The distribution of phenotypes was in agreement with codominant single gene inheritance. The Chi-square (˜ ) test revealed that the population is under Hardy-Weinberg equilibrium.

Genetic variation of some goat populations in Ethiopia by means of blood protein polymorphism

Genetic variability of 298 individuals from four indigenous goat types (Afar, Hararghe Highland, Western Highland and Western Lowland of Ethiopia), two exotic breeds (Toggenburg and Anglo-Nubian) and three crossbreed populations (crosses between the exotic breeds and Hararghe Highland and Somali goat types) were investigated. The red blood cell lysates and plasma proteins were analyzed by starch gel electrophoresis. From a total of five loci studied, two were found to be polymorphic. Two alleles were detected at each of Haemoglobin (Hb) and Transferrin (Tf) loci. Only one allele was detected at each of the loci Carbonic anhydrase (CA), Albumin (Al) and Post Transferrin (PTF) in all the populations of goats studied. In most cases, the observed genotypic frequencies were not significantly different from that expected under the Hardy-Weinburg equilibrium. The proportion of polymorphic loci (P%) varied between 20.0% and 40.0%, with mean number of alleles per locus between 1.2 and 1.4, and expected heterozygosities (HE) between 0.030 and 0.177 while mean observed heterozygosities (HO) were between 0.032 to 0.217. Among the three groups of goat populations, higher variability was found in crossbred populations. Afar goat type was more variable (HO=6.7%) among the indigenous goat types. Cluster analysis based on Nei’s standard genetic distance and the unweighted pair-group method using arithmetic averages (UPGMA) revealed low level of genetic distance among populations. The results indicated a higher proportion of genetic variation between populations. Keywords: Afar goat, Ethiopia, Hararghe goat, Western Highland goat, Western Lowland goat.

Systems Genetics of Metabolism: The Use of the BXD Murine Reference Panel for Multiscalar Integration of Traits

Metabolic homeostasis is achieved by complex molecular and cellular networks that differ significantly among individuals and are difficult to model with genetically engineered lines of mice optimized to study single gene function. Here, we systematically acquired metabolic phenotypes by using the EUMODIC EMPReSS protocols across a large panel of isogenic but diverse strains of mice (BXD type) to study the genetic control of metabolism. We generated and analyzed 140 classical phenotypes and deposited these in an open-access web service for systems genetics (www.genenetwork.org). Heritability, influence of sex, and genetic modifiers of traits were examined singly and jointly by using quantitative-trait locus (QTL) and expression QTL-mapping methods. Traits and networks were linked to loci encompassing both known variants and novel candidate genes, including alkaline phosphatase (ALPL), here linked to hypophosphatasia. The assembled and curated phenotypes provide key resources and exemplars that can be used to dissect complex metabolic traits and disorders.

Analysis of genetic variation in normal feathered, naked neck and fulani-ecotype nigerian indigenous chickens based on haemoglobin polymorphism

Haemoglobin polymorphism was investigated in 50 normal feathered, 33 naked neck and 42 Fulani-ecotype Nigerian indigenous chickens. Haemoglobin typing was carried out using cellulose acetate electrophoresis. Two co-dominant haemoglobin alleles (HbA and HbB) were found in the chickens. From the electrophoretic band patterns, three genotypes (HbAA, Hband HbBB) were observed. The frequencies of the A and B genes were 0.68 and 0.32; 0.71 and 0.29; 0.75 and 0.25 for normal feathered, naked neck and Fulani-ecotype chickens respectively. The corresponding genotype frequencies for AA, AB, and BB in the three chicken populations were 0.54, 0.28 and 0.18; 0.58, 0.27and 0.15; 0.62, 0.26 and 0.12 respectively. The gene and genotype frequencies of naked neck and Fulani-ecotype birds were in Hardy-Weinberg equilibrium while those of normal feathered birds deviated significantly from the theoretical proportions. The average amount of heterozygosity at haemoglobin locus was 0.41. The results obtained could serve as a reference point in the genetic improvement of indigenous chickens using biochemical markers.