Abnormal hemoglobins among Kurdish population of Western Iran: hematological and molecular features

The type and frequency of structural hemoglobin variants and their hematological and molecular characteristics were identified using PCR-RFLP and sequencing techniques in 66 individuals from 33 unrelated families who referred to the two clinics of Kermanshah University of Medical Sciences from 2005 to 2006. We detected 28 subjects carrier for Hb D-Punjab (42.4%), 21 individuals carrier of Hb Q-Iran (31.8%), 12 subjects heterozygous for Hb Setif (18.2%), four cases with sickle cell disease (6.1%), and one case with Hb C (1.5%). All β^S genes (4 genes) were linked to the Benin haplotype with negative Taq I site 5′ to γ^A gene. All β^D-Punjab genes (29 genes) were in linkage disequilibrium with haplotype I. The only β^C chromosome was linked to haplotype II. Both β⁰-thalassemia chromosomes with CD15 (G → A) mutation had haplotype background I. Three β⁺-thalassemia chromosomes with IVSI.110 (G → A) mutation were associated with haplotype I [+ − − − − + +]. In turn, the three β-thalassemia chromosomes with IVS II.1 G → A mutation were associated with atypical haplotype [− + + + + + −]. Hematological indices of carriers of Hb D-Punjab, Hb Q-Iran and Hb Setif were lower than those reported for normal individuals. For the first time, we have reported the haplotype background of β^S gene among Kurdish population of Iran. Our results revealed that Hb D-Punjab is the most prevalent β-globin chain structural variant in this area and that is followed in frequency by an α-chain variant, Hb Q-Iran. The result of present study is useful for clinical management and the establishment of screening programmes in Western Iran.     

Abnormal hemoglobins in the Silk Road region of China

Summary A review is presented of the occurrence of 24 abnormal hemoglobins (13 -chain variants and 11 -chain variants) in populations in the Silk Road area of Northwestern China. Most frequently occurring were Hb D-Punjab [21(GH4)GluGln] in Uygurs, Kazaks, and Khalkhas, Hb G-Taipei [22(B4)GluGly] in persons of the Han nationality, and Hb G-Coushatta [22 (B4)GluAla] in the Uygurs, Kazaks, Hans, and related nationalities. The data suggest that these variants likely originated in Central Asia, in the Han nationality of China, and in the minorities of northern China, respectively. Other variants occurred at considerably lower frequencies and were imported from other countries or arose as independent mutations. Two variants [Hb Tashikuergan or 19(AB1)AlaGlu; Hb Tianshui or 39(C5) GlnArg] were observed for the first time. The data from this study of the many variants support the movements of various populations in this area, as reported in numerous historical documents.     

Analysis of various classical genetic markers in the Costa Rica population

A study of several loci blood groups (ABO, Diego, Duffy, Kell, Kidd, Lewis, Lutheran, MNSs, P, Rhesus and Secretor), and Hp serum protein was carried out on a sample of 2,196 unrelated Costa Rican individuals of both sexes. Data was classified and analyzed according to geographic regions. Gene frequencies and the goodness of fit to Hardy-Weinberg equilibrium were estimated by the maximum likelihood method. A geographic structuring was observed in the Costa Rican population. All the regions of Costa Rica show higher heterozigosity values than the ones observed in the indigenous Costa Rican groups, but similar or slightly higher than the ones observed in the Spanish populations. The genetic distance analysis evidenced that the regions of Costa Rica group close to each other in intermediate positions between the Amerindians and the Spanish, fact that is coherent with the statement that attributes a intermediate origin to the general population of Costa Rica. The data contradicts the idea that the Central region has a radically different population than the rest of the country. The outcome of these markers revealed poor values of exclusion probability in forensic and paternity cases, which confirms the importance of their replacement for DNA markers in the outlines of human identification of judicial investigation systems. These results are similar to other studies made in Latin American populations.     

Glycosylated hemoglobins in humans and various animal species

The quantity of glycosylated hemoglobins and proteins from blood serum of rabbits, fishes, minks and guinea-pigs is investigated. The content of glycosylated hemoglobins in newborns and healthy adults is compared with that of animals. The colorimeter method of defining glycosylate proteins is used in the test. Three groups are isolated by the quantity of glycosylated proteins. These are the following: the first group with the low content--minks, rabbits, guinea-pigs, the second one with the mean content--healthy newborn and grown-ups and the third group with the high content--fishes. The obtained results evidence for possibility of protein glycosylation not only in human beings but also in animals and fishes.     

Noninvasive genetic assessment of brown bear population structure in Bulgarian mountain regions

The Balkans are one of the last large refugia for brown bear (Ursus arctos) populations in Europe, and Bulgaria, in particular, contains relatively large areas of suitable brown bear habitat and a potential population of more than 600 individuals. Despite this, the majority of brown bear research remains focused on bear populations in Central and Western Europe. We provide the first assessment of genetic population structure of brown bears in Bulgaria by analysing tissue samples (n = 16) as well as samples collected with noninvasive genetic methods, including hair and faecal samples (n = 189 and n = 163, respectively). Sequence analysis of a 248 base pair fragment of the mitochondrial control region showed that two highly divergent mitochondrial European brown bear lineages form a contact zone in central Bulgaria. Furthermore, the analysis of 13 polymorphic microsatellite markers identified 136 individuals and found substantial genetic variability (H_e = 0.74; N_A = 8.9). The combination of both genetic markers revealed the presence of weak genetic substructure in the study area with considerable degrees of genetic admixture and the likely presence of migration corridors between the two subpopulation in the Rhodope Mountains and Stara Planina as evidenced from the genetic detection of two male long-distance dispersers. A detailed assessment from densely collected samples in the Rhodope Mountains resulted in a population size estimate of 315 (95% CI = 206–334) individuals, indicating that not all available habitat is presently occupied by bears in this region. Efficient management plans should focus on preserving connectivity of suitable habitats in order to maintain gene flow between the two Bulgarian brown bear subpopulations.     

Substance P levels in various regions of the rat central nervous system after acute and chronic morphine treatment

Substance P levels were measured in various CNS regions from rats treated acutely and chronically with morphine. There was no observable effect in the group treated with an acute dose of morphine (10 mg/kg) and sacrificed after 2 h. After 35 days chronic treatment with increasing doses of the drug, the rats were divided into three groups and sacrificed 2 h, 24 h and 7 days after the last injection. The substance P level was increased in the corpus striatum 2 h and 24 h and in the medulla oblongata and dorsal part of the spinal cord 2 h after withdrawal. Seven days after the last injection the levels had returned to normal in these areas. No effects were observed in the cerebral cortex, the hypothalamus or the ventral spinal cord at any time of measurement. Earlier studies have demonstrated that morphine inhibits release of substance P. The observed increase in tissue levels after long-term treatment is therefore interpreted as an accumulation of substance P in the neurons.     

Morphological differentiation of the central visual cells R7/8 in various regions of the blowfly eye

The central rhabdomeres in the retina of the blowfly Calliphora erythrocephala and the house fly Musca domestica are not structurally uniform. In Calliphora, four classes of central rhabdomeres were found; they are formed by a total of seven types of central visual cells, clearly distinguished by the following structural features: length of the rhabdomeres R7 or R8, position of the nucleus, rhabdomere twist, fine structure in the R7/R8 transition region, and cross-sectional area of the rhabdomeres. In the lateral part of the eye only the most common central-rhabdomere class, ‘sl.’ is present, whereas in the frontal and dorsal parts classes ‘sl’ and ‘ls’ are found in a particular numerical ratio. Near the frontal eye margin the rare class ‘per’ also appears, with two separate rhabdomeres, R7per and R8s; the morphological properties of R7per are midway between those of peripheral and central visual cells. The special ommatidia at the dorsal margin of the eye are characterized by the central rhabdomeres ‘marg’. The known functional properties of the visual cells in the fly eye can be readily assigned to these classes (Table 1, Fig. 12). The non-uniform distribution of the various kinds of central rhabdomeres suggests functional differentiation of the eye region.     

种群微卫星DNA分析中样本量对各种遗传多样性度量指标的影响

我们以中国飞蝗种群的微卫星遗传分析数据为例 ,评估了取样对种群遗传多样性指标的影响 ,结果显示 :样本大小与所观测到的每位点等位基因数、平均等位基因数及基因丰富度指数均呈显著正相关 ,而与期望杂合度无显著相关 ;微卫星位点多态性的高低直接影响所观测到的种群基因丰富度及其检测所需的样本量 ;对大多数种群遗传和分子生态学研究而言 ,30 - 5 0个个体是微卫星DNA分析所需要的最小样本量。基因丰富度经过稀疏法或多次随机抽样法校正后 ,可适用于瓶颈效应等种群历史数量变动的检测。另外 ,在研究中 ,还应避免采集时间的不同及样本的性比构成所可能造成的对种群遗传结构的影响     

Ionizing radiation and genetic risks. I. Epidemiological, population genetic, biochemical and molecular aspects of Mendelian diseases

This paper reviews the currently available information on naturally occurring Mendelian diseases in man; it is aimed at providing a background and framework for discussion of experimental data on radiation-induced mutations (papers II and III) and for the estimation of the risk of Mendelian disease in human populations exposed to ionizing radiation (paper IV). Current consensus estimates indicate that a total of about 125 per 10(4) livebirths are directly affected by one or another naturally occurring Mendelian disease (autosomal dominants, 95/10(4); X-linked ones, 5/10(4); and autosomal recessives, 25/10(4). These estimates are conservative and take into account conditions which are very rare and for which prevalence estimates are unavailable. Most, although not all, of the recognized "common" dominants have onset in adult ages while most sex-linked and autosomal recessives have onset at birth or in childhood. Autosomal dominant and X-linked diseases (i.e., the responsible mutant alleles) presumed to be maintained in the population due to a balance between mutation and selection are the ones which may be expected to increase in frequency as a result of radiation exposures. Viewed from this standpoint, the above assumption seems safe only for a small proportion of such diseases; for the remainder, there is no easy way to discriminate between different mechanisms that may be responsible or to rigorously exclude some in favor of some others. Mutations in genes that code for enzymic proteins are more often recessive in contrast to those that code for non-enzymic proteins, which are more often dominant. At the molecular level, with recessives, a wide variety of changes is possible and these include specific types of point mutations, small and large intragenic deletions, multilocus deletions and rearrangements. In the case of dominants, however, the kinds of recoverable point mutations and deletion-type changes are less extensive because of functional constraints. The mutational potential of genes varies, depending on the gene, its size, sequence content and arrangement, location and its normal functions, and can be grouped into three groups: those in which only point mutations have been found to occur, those in which only deletions or other gross changes have been recovered and those in which both kinds of changes are known. Molecular data are available for about 75 Mendelian conditions and these suggest that in approximately 50% of them, the changes categorized to date are point mutations and in the remainder, intragenic deletions or other gross changes; there does not seem to be any fundamental difference between dominants and recessives with respect to the underlying molecular defect.(ABSTRACT TRUNCATED AT 400 WORDS)