Linkage group-chromosome correlation in Podospora anserina

Summary Two reciprocal translocations have been studied in an attempt to establish a one-to-one assignment of the seven linkage groups of P. anserina to specific chromosomes. Genetical data demonstrated clearly the relationships of the two translocations with three linkage groups. Cytological observations at meiosis in crosses heterozygous for the chromosomal interchanges showed the characteristic cross-like figures and confirmed the fact that the two translocations had one chromosome in common. The correspondence of the three largest chromosomes, including the one bearing the nucleolar organizer, with three well known linkage groups has thus been established. Evidence is also given that loci exhibiting a percentage of second division segregation as high as 98% are not at the end of the chromosomes.     

Genetical control of the allozymes in juniper (Juniperus excelsa Bieb.) of the Crimea

Genetical control of nine enzyme systems has been studied in preserved juniper species (Juniperus excelsa Bieb.) of the natural population of the mountain Crimea. Isozymes were extracted from the haploid seed endosperms and separated elecrophoretically. As a result 16 loci have been identified. Fourteen of them were polymorphic (14--Gdh, Got-1, Mdh-1, Mdh-2, Mdh-3, Acp-1, Acp-2, Acp-3, Lap-1, Dia-1, Fdh, Sod-1, Sod-2, Sod-3). Analysis of the allele segragation of the heterozygous trees confirmed their monogenic inheritance.     

Genetic control of isozymes in European spruces (Picea abies (L) Karst) of the Ukrainian Carpathian mountains

Genetical control of the enzymes GOT, GDH, DIA, MDH, SOD, FDH, ADH, ACP and LAP has been studied in nine natural Carpathian populations of Norway spruce (Picea abies (L.) Karst.) using polyacrylamide gel elecrophoresis and analysis of isozyme variability in 346 trees. Seventy one allel products of 20 gene loci have been clearly established. Segregation analysis of the revealed allele variants confirms their monogenic inheritance.     

Incidence and Prevalence of Chronic Obstructive Pulmonary Disease among Aboriginal Peoples in Alberta,Canada

Background

Chronic obstructive pulmonary disease (COPD) is a major respiratory disorder, largely caused by smoking that has been linked with large health inequalities worldwide. There are important gaps in our knowledge about how COPD affects Aboriginal peoples. This retrospective cohort study assessed the epidemiology of COPD in a cohort of Aboriginal peoples relative to a non-Aboriginal cohort.

Methods

We used linkage of administrative health databases in Alberta (Canada) from April 1, 2002 to March 31, 2010 to compare the annual prevalence, and the incidence rates of COPD between Aboriginal and non-Aboriginal cohorts aged 35 years and older. Poisson regression models adjusted the analysis for important sociodemographic factors.

Results

Compared to a non-Aboriginal cohort, prevalence estimates of COPD from 2002 to 2010 were 2.3 to 2.4 times greater among Registered First Nations peoples, followed by the Inuit (1.86 to 2.10 times higher) and the Métis (1.59 to 1.67 times higher). All Aboriginal peoples had significantly higher COPD incidence rates than the non-Aboriginal group (incidence rate ratio [IRR]: 2.1; 95% confidence interval [CI]: 1.97, 2.27). COPD incidence rates were higher in First Nation peoples (IRR: 2.37; 95% CI: 2.19, 2.56) followed by Inuit (IRR: 1.92; 95% CI: 1.64, 2.25) and Métis (IRR: 1.49; 95% CI: 1.32, 1.69) groups.

Conclusions

We found a high burden of COPD among Aboriginal peoples living in Alberta; a province with the third largest Aboriginal population in Canada. Altogether, the three Aboriginal peoples groups have higher prevalence and incidence of COPD compared to a non-Aboriginal cohort. The condition affects the three Aboriginal groups differently; Registered First Nations and Inuit have the highest burden of COPD. Reasons for these differences should be further explored within a framework of social determinants of health to help designing interventions that effectively influence modifiable COPD risk factors in each of the Aboriginal groups.     

Isolation and characteristics of new mutants of Saccharomyces cerevisiae with increased spontaneous mutability]

To isolate some new genes controlling the process of spontaneous mutagenesis, a collection of 16 yeast strains with enhanced rate of spontaneous canavanine resistant mutations was obtained. Genetical analysis allowed to define that the mutator phenotype of these strains is due to a single nuclear mutation. Such mutations were called hsm (high spontaneous mutagenesis). Recombinational test showed that 5 mutants under study carried 5 nonallelic mutations. It was revealed that the mutation hsm3-1 is a nonspecific mutator elevating the rate of both spontaneous canavanine resistant mutations and the frequency of reversions in mutations lys1-1 and his1-7. Genetical analysis revealed that mutation hsm3-1 is recessive. The study of cross sensitivity of mutator strains to physical and chemical mutagens demonstrated that 12 of 16 hsm mutants were resistant to the lethal action of UV, gamma rays and methylmethanesulfonate, and 4 mutants were only sensitive to these factors. Possible nature of hsm mutations is discussed.     

水稻品种对白背飞虱的抗源筛选及其抗性遗传分析

通过抗性鉴定,筛选出6个抗白背飞虱的国内品种:鬼衣谷、大花谷、大齐谷、便谷、滇瑞336.3和HA 79317-7(前4个品种均系云南地方品种)。遗传分析证明,这6个品种对白背飞虱的抗性均受单显性基因控制。HA 79317-7的抗性基因与Wbph1等位,滇瑞336-3的抗性基因与Wbph2等位。鬼衣谷、大齐谷、大花谷和便谷的抗性基因均与Wbph1、Wbph2非等位。它们与Wbph3、Wbph5的等位关系还有待进一步研究。     

Personal orientations towards Australian national identity among British-born residents

An area of long-standing interest in sociological studies of nationality and ethnicity has been the implications of widespread cross-border movements of peoples for cultural identity. One important stream of research has been concerned with peoples who have moved to a new country that is culturally different from their “homeland”. Yet, far less attention has typically been given to those who shift to a country that is culturally alike. The study examines how peoples who have relocated from Great Britain to Australia feel about various ideas at the heart of contemporary debates about Australian national identity. Drawing on data from a 2001 survey of Australian national identity, analysis indicated that (i) British-born residents differ from the Australian-born in how their attitudes to key ideas about Australian national identity are “packaged” together, and (ii) among the British-born, views about Australian national identity vary across subgroups with different configurations of national pride.     

Genetical genomics in humans and model organisms

Genetical genomics has been proposed to map loci controlling gene-expression differences (eQTLs) that might underlie functional trait variation. We briefly review the studies in model species and conclude that, although they successfully demonstrate the utility of genetical genomics, they are too limited to unlock the full potential of this approach and some results should be interpreted with caution. We subsequently elaborate on two recent studies that use this approach in humans. The many differences between these studies complicate meaningful comparisons between them. A joint analysis of the two experiments offers some scope for more powerful genetical genomics.     

Variation in anthropometric characters and their relationship with climatic factors: a study on the peoples of Arunachal Pradesh, India

In the present study an attempt has been made to examine the anthropometric variation and the relationship of anthropometric variables with climatic factors among the peoples of Arunachal Pradesh, India. The distance analysis does not seem to provide any interesting corroboration between anthropometric data and the intra- and intergroup relationship. A similar trend has also been noticed while analysing the correlation coefficient between two indices (i.e. the cephalic and total facial index). The present study suggests that the climatic factors are playing an important role in regulating the variation of anthropometric characters among the different population groups of Arunachal Pradesh.     

Attempt at quantitative estimation of genetic effects of chemical pollution of atmospheric air in urban populations]

Epidemiological investigation of spontaneous abortions and congenital anomalies in three towns of Ukraine has shown that mutation rate in Mariupol, the most contaminated town, as compared with relatively clean town is essentially higher. Genetical consequences due to environmental chemical pollution in Mariupol proved to be equivalent to the chronic influence of ionizing radiation for 30 years in the dose of 230 REM.     

Genetical features of influenza virus A (H1N1) strain that caused the 2009 pandemic

Genetical features of the A(H1N1) influenza virus strain that caused the 2009 pandemic are analyzed in the review. Mutations typical for this strain, unique and similar to influenza viruses of swine, avian and seasonal types, and phenotypic (pathologic) features associated with them, that are experimentally confirmed, are described. A possibility of reassortation of avian and swine influenza viruses and possible epidemiologic consequences are discussed.     

Isolation and characteristics of Chinese hamster cells resistant to colchicine

Several ClchR clones of CHO-K1 have been isolated by a single- and multistep selection. They are distinct from each other both in the level of colchicine resistance and in the phenotypic stability of this feature. Fluctuation tests showed that the generation of drug resistant variants in the wild type population was random and did not depend on the action of selective agent. The rate of spontaneous occurrence of these variants was approximatley 1.79 x 10(-6) per cell per generation. Treatment with MNNG enhanced the frequency of ClchR variants by 100 fold. Cytotoxic effect of Clch on resistant cells has been potentiated by non-ionic detergent Tween 80. All the stable resistant clones appeared to be cross resistant to unrelated drugs such as actinomycin D, ethydium bromide and aminopterine . These two observations allow to suggest the alteration of membrane permeability as a mechanism of resistance to Clch . Genetical mechanisms of Clch -resistance of cells are discussed.     

Immunogenetic markers in populations of Komi

Immunological markers of genetic systems AB0, MNSs, Rhesus (CDE), P. Lewis, Kell-Cellano, Diffy and ABH-secretion were analyzed in the two populations of Komi and in one population of Komi-Permyaks. It has been shown that the gene pools of these three groups are europeoid on the whole. Based on analysis of genetic distances, it was discovered that Komi and Komi-Permyaks are closer to the Finnish speaking peoples than the others. We have described common and specific genetic features of these three populations.     

The Genetic Legacy of the Expansion of Turkic-Speaking Nomads across Eurasia

The Turkic peoples represent a diverse collection of ethnic groups defined by the Turkic languages. These groups have dispersed across a vast area, including Siberia, Northwest China, Central Asia, East Europe, the Caucasus, Anatolia, the Middle East, and Afghanistan. The origin and early dispersal history of the Turkic peoples is disputed, with candidates for their ancient homeland ranging from the Transcaspian steppe to Manchuria in Northeast Asia. Previous genetic studies have not identified a clear-cut unifying genetic signal for the Turkic peoples, which lends support for language replacement rather than demic diffusion as the model for the Turkic language’s expansion. We addressed the genetic origin of 373 individuals from 22 Turkic-speaking populations, representing their current geographic range, by analyzing genome-wide high-density genotype data. In agreement with the elite dominance model of language expansion most of the Turkic peoples studied genetically resemble their geographic neighbors. However, western Turkic peoples sampled across West Eurasia shared an excess of long chromosomal tracts that are identical by descent (IBD) with populations from present-day South Siberia and Mongolia (SSM), an area where historians center a series of early Turkic and non-Turkic steppe polities. While SSM matching IBD tracts (> 1cM) are also observed in non-Turkic populations, Turkic peoples demonstrate a higher percentage of such tracts (p-values ≤ 0.01) compared to their non-Turkic neighbors. Finally, we used the ALDER method and inferred admixture dates (~9th–17th centuries) that overlap with the Turkic migrations of the 5th–16th centuries. Thus, our results indicate historical admixture among Turkic peoples, and the recent shared ancestry with modern populations in SSM supports one of the hypothesized homelands for their nomadic Turkic and related Mongolic ancestors.     

Variation of DAT1 VNTR alleles and genotypes among old ethnic groups in Mesopotamia to the Oxus region

Variation of a VNTR in the DAT1 gene in seven ethnic groups of the Middle East was used to infer the history and affinities of these groups. The populations consisted of Assyrian, Jewish, Zoroastrian, Armenian, Turkmen, and Arab peoples of Iran, Iraq, and Kuwait. Three hundred forty subjects from these seven ethnic groups were screened for DAT1. DAT1 VNTR genotyping showed 3, 6, 7, 8, 9, 10, 11, and 12 alleles in the samples. Analysis of these data revealed differentiation and relationship among the populations. In this region, which covers an area of 2-2.5 million km2, the influence of geography and especially of linguistic characteristics has had potentially major effects on differentiation. Religion also has played a major role in imposing restrictions on some ethnic groups, who as a consequence have maintained their community. Overall, these ethnic groups showed greater heterogeneity compared to other populations.     

藏族生物人类学研究回顾

藏族生活在具有世界屋脊之称的青藏高原,特殊的生态环境和特殊的文化背景造就了藏族特殊的适应高原缺氧机制和体质特征,引起了国内外学者的广泛关注和浓厚的研究兴趣。本文从国内外数据库收集了492篇国内外杂志发表的关于藏族人类学研究方面的论文。通过统计、分析并结合我们的工作,初步回顾了30年藏族人类学研究,重点分析了藏族与汉族的族源关系。这些文献显示,从体质特征、血型、分子生物学和考古材料等方面都证明藏族是中华民族大家庭中不可缺少的的一员。本文最后展望了藏族生物人类学今后的发展。     

An Expression QTL of Closely Linked Candidate Genes Affects pH of Meat in Chickens

Genetical genomics has been suggested as a powerful approach to study the genotype–phenotype gap. However, the relatively low power of these experiments (usually related to the high cost) has hindered fulfillment of its promise, especially for loci (QTL) of moderate effects.One strategy with which to overcome the issue is to use a targeted approach. It has two clear advantages: (i) it reduces the problem to a simple comparison between different genotypic groups at the QTL and (ii) it is a good starting point from which to investigate downstream effects of the QTL. In this study, from 698 F2 birds used for QTL mapping, gene expression profiles of 24 birds with divergent homozygous QTL genotypes were investigated. The targeted QTL was on chromosome 1 and affected initial pH of breast muscle. The biological mechanisms controlling this trait can be similar to those affecting malignant hyperthermia or muscle fatigue in humans. The gene expression study identified 10 strong local signals that were markedly more significant compared to any genes on the rest of the genome. The differentially expressed genes all mapped to a region <1 Mb, suggesting a remarkable reduction of the QTL interval. These results, combined with analysis of downstream effect of the QTL using gene network analysis, suggest that the QTL is controlling pH by governing oxidative stress. The results were reproducible with use of as few as four microarrays on pooled samples (with lower significance level). The results demonstrate that this cost-effective approach is promising for characterization of QTL.     

Temperature-Sensitive Pleiotropic Revertants from a Mutant in the AROM Gene Cluster of NEUROSPORA CRASSA

Genetical and biochemical studies have been performed with revertants induced in a polyaromatic mutant (No. 58) in the arom gene cluster of Neurospora crassa. In addition to complete and partial revertants able to grow on minimal at both 25 degrees and 35 degrees , temperature-sensitive revertants capable of growth on minimal at 25 degrees but not at 35 degrees have been recovered. One of these revertants has been shown to lack biosynthetic dehydroquinase activity at both temperatures (utilizing the inducible catabolic isozyme for growth at 25 degrees ), to have dehydroshikimate reductase activity only at 25 degrees , and to form an arom aggregate having a molecular weight approximately one-half that of wild type. These results are interpreted as indicating that pleiotropic mutants in the arom gene cluster can result from missense mutations, as well as from nonsense mutations as indicated in previous studies.     

The denied land rights of the indigenous peoples and their endangered livelihood and survival: the case of the Nuba of the Sudan

The current situation of indigenous peoples in the Sudan is the result of the independent state's adoption of land and other policies identical to those introduced by colonialists more than a century ago. The Sudanese state has not only unwittingly maintained some colonial coercive institutions and policies but it has introduced more aggressive ones and brutally deployed them against its indigenous peoples, particularly the Nuba. In the light of this, this paper attempts to demonstrate analytically how some historical and contemporary socio-political dynamics have continued systematically to deprive these indigenous Nuba peoples of their customary land, and to assess to what extent the recently concluded Comprehensive Peace Agreement (CPA) has been successful in addressing the land question as one of the root causes of the recurring civil wars in the Sudan in general and in the Nuba Mountains in particular.     

Absence of the Asian-specific region V mitochondrial marker in Native Beringians.

The Asian-specific 9-bp deletion between the genes for mitochondrial cytochrome oxidase II and lysine transfer RNA has been used to trace aboriginal human movements out of Southeast Asia and into portions of the South Pacific. Although it has been used to estimate the number of independent lineages that occur in the New World, it has not been studied in native peoples of the Beringian region. Thus, we have used PCR to amplify and compare the lengths of DNA segments surrounding this deletion in native peoples of Beringia and the adjacent regions, as well as natives of the Altai Mountains of Southwestern Siberia. Of the 176 individuals analyzed here, the deletion was found in only 3 of 25 individuals from the Ust-Kan region of the Altai Mountains. We comment on the distribution of this marker and on potential relationships between Beringians and other Native American groups in which this marker has been surveyed. One Chukchi possessed three copies of the 9-bp sequence, which suggests (1) that the number of copies of this sequence in humans may be more variable than had been believed and (2) that a mechanism of replication based on tandem duplication may be a potential explanation for the origin of this length mutation in humans.