Genetics

Professional journal providing news and analysis on field of genetics. Features special reports such as policy reviews and awards.

Articles from Vol. 178, No. 1, January

A Bayesian Method for Simultaneously Detecting Mendelian and Imprinted Quantitative Trait Loci in Experimental Crosses of Outbred Species
ABSTRACTGenomic imprinting is interpreted as a phenomenon, in which some genes inherited from one parent are not completely expressed due to modification of the genome caused during gametogenesis. Subsequently, the expression level of an allele at the...
Accuracy of Genomic Selection Using Different Methods to Define Haplotypes
ABSTRACTGenomic selection uses total breeding values for juvenile animals, predicted from a large number of estimated marker haplotype effects across the whole genome. In this study the accuracy of predicting breeding values is compared for four different...
African Drosophila Melanogaster and D. Simulans Populations Have Similar Levels of Sequence Variability, Suggesting Comparable Effective Population Sizes
ABSTRACTDrosophila melanogaster and D. simulans are two closely related species with a similar distribution range. Many studies suggested that D. melanogaster has a smaller effective population size than D. simulans. As most evidence was derived from...
A Gain-of-Function Suppressor Screen for Genes Involved in Dorsal-Ventral Boundary Formation in the Drosophila Wing
ABSTRACTThe Drosophila wing primordium is subdivided into a dorsal (D) and a ventral (V) compartment by the activity of the LIM-homeodomain protein Apterous in D cells. Cell interactions between D and V cells induce the activation of Notch at the DV...
A Genetic Selection for Neurospora Crassa Mutants Altered in Their Light Regulation of Transcription
ABSTRACTTranscription of the Neurospora crassa gene con-10 is induced during conidiation and following exposure of vegetative mycelia to light, but light activation is transient due to photoadaptation. We describe mutational analyses of photoadaptation...
An Accurate Model for Genetic Hitchhiking
ABSTRACTWe suggest a simple deterministic approximation for the growth of the favored-allele frequency during a selective sweep. Using this approximation we introduce an accurate model for genetic hitchhiking. Only when Ns < 10 (N is the population...
An Unstable Targeted Allele of the Mouse Mitf Gene with a High Somatic and Germline Reversion Rate
ABSTRACTThe mouse Mitf gene encodes a transcription factor that is regulated by serine phosphorylation and is critical for the development of melanin-containing pigment cells. To test the role of phosphorylation at a particular serine, S73 in exon 2...
Biased Distributions and Decay of Long Interspersed Nuclear Elements in the Chicken Genome
ABSTRACTThe genomes of birds are much smaller than mammalian genomes, and transposable elements (TEs) make up only 10% of the chicken genome, compared with the 45% of the human genome. To study the mechanisms that constrain the copy numbers of TEs, and...
Characterization of Interactions between and among Components of the Meiotic Silencing by Unpaired DNA Machinery in Neurospora Crassa Using Bimolecular Fluorescence Complementation
ABSTRACTBimolecular fluorescence complementation (BiFC) is based on the complementation between two nonfluorescent fragments of the yellow fluorescent protein (YFP) when they are united by interactions between proteins covalently linked to them. We have...
Chromatin-Associated Genes Protect the Yeast Genome from Tyl Insertional Mutagenesis
ABSTRACTChromosomal genes modulate Ty retrotransposon movement in the genome of Saccharomyces cerevisiae. We have screened a collection of 4739 deletion mutants to identify those that increase Ty1 mobility (Ty1 restriction genes). Among the 91 identified...
Cin-4, a Gene with Homology to Topoisomerase II, Is Required for Centromere Resolution by Cohesin Removal from Sister Kinetochores during Mitosis
ABSTRACTThe back-to-back geometry of sister kinetochores is essential in preventing loss or damage of chromosomes during mitosis. Kinetochore orientation is generated in part by a process of resolving kinetochores at the centromere (centromere resolution)...
Cypress Surrogate Mother Produces Haploid Progeny from Alien Pollen
ABSTRACTAlthough most living organisms reproduce sexually, some have developed a uniparental reproduction where the embryo usually derives from the female parent. A unique case of paternal apomixis in plants has been recently reported in Cupressus dupreziana,...
Cytonuclear Genic Incompatibilities Cause Increased Mortality in Male F^sub 2^ Hybrids of Nasonia Giraulti and N. Vitripennis
ABSTRACTThe haplodiploid wasp genus Nasonia is a promising model for studying the evolution of genic incompatibilities due to the existence of interfertile species and haploid males. The latter allows for significantly reducing the sample size required...
Determination of Mitochondrial Genetic Diversity in Mammals
ABSTRACTMitochondrial DNA (mtDNA) is one of the most popular population genetic markers. Its relevance as an indicator of population size and history has recently been questioned by several large-scale studies in animals reporting evidence for recurrent...
Development and Evaluation of a Genetics Literacy Assessment Instrument for Undergraduates
ABSTRACTThere is continued emphasis on increasing and improving genetics education for grades K-12, for medical professionals, and for the general public. Another critical audience is undergraduate students in introductory biology and genetics courses....
Differential Regulation of Anaphase Promoting Complex/Cyclosome Substrates by the Spindle Assembly Checkpoint in Saccharomyces Cerevisiae
ABSTRACTThe anaphase promoting complex (APC) targets proteins for degradation to promote progression through the cell cycle. Here we show that Clb5, an APC^sup Cdc20^ substrate, is degraded when the spindle checkpoint is active, while other APC^sup Cdc20^...
Distinct Activities of the Germline and Somatic Reproductive Tissues in the Regulation of Caenorhabditis Elegans' Longevity
ABSTRACTThe two parts of the Caenorhabditis elegans reproductive system, the germ cells and the somatic reproductive tissues, each influence the life span of the animal. Removing the germ cells increases longevity, and this life span extension requires...
Dual Involvement of CbrAB and NtrBC in the Regulation of Histidine Utilization in Pseudomonas Fluorescens SBW25
ABSTRACTPseudomonas fluorescens SBW25 is capable of growing on histidine as a sole source of carbon and/or nitrogen. Previous work showed that the two-component regulatory system CbrAB is required for expression of the histidine utilization (hut) locus...
Empirical Tests of the Reliability of Phylogenetic Trees Constructed with Microsatellite DNA
ABSTRACTMicrosatellite DNA loci or short tandem repeats (STRs) are abundant in eukaryotic genomes and are often used for constructing phylogenetic trees of closely related populations or species. These phylogenetic trees are usually constructed by using...
Enhancer Blocking and Transvection at the Drosophila Apterous Locus
ABSTRACTIntra- and interchromosomal interactions have been implicated in a number of genetic phenomena in diverse organisms, suggesting that the higher-order structural organization of chromosomes in the nucleus can have a profound impact on gene regulation....
Estimating the Per-Base-Pair Mutation Rate in the Yeast Saccharomyces Cerevisiae
ABSTRACTAlthough mutation rates are a key determinant of the rate of evolution they are difficult to measure precisely and global mutations rates (mutations per genome per generation) are often extrapolated from the per-base-pair mutation rate assuming...
Examination of Interchromosomal Interactions in Vegetatively Growing Diploid Schizosaccharomyces Pombe Cells by Cre/loxP Site-Specific Recombination
ABSTRACTThe probability with which different regions of a genome come in contact with one another is a question of general interest. The current study addresses this subject for vegetatively growing diploid cells of fission yeast Schizosaccharomyces...
Few Mendelian Genes Underlie the Quantitative Response of a Forest Tree, Eucalyptus Globulus, to a Natural Fungal Epidemic
ABSTRACTFoliar fungal pathogens from the genus Mycosphaerella affect eucalypts in natural forests and plantations worldwide. QTL analysis was conducted to dissect the genetic control of resistance in Eucalyptus globulus to a natural infection by Mycosphaerella...
Genetic Design and Statistical Power of Nested Association Mapping in Maize
ABSTRACTWe investigated the genetic and statistical properties of the nested association mapping (NAM) design currently being implemented in maize (26 diverse founders and 5000 distinct immortal genotypes) to dissect the genetic basis of complex quantitative...
Genetic Linkage Map of the Nucleolus Organizer Region in the Soybean
ABSTRACTSimple polymorphisms in ribosomal DNA repeats in the nucleolus organizer region (NOR) permitted the development of markers for the genetic mapping of the soybean NOR. The markers map to the top end of soybean linkage group F, one of either telomeric...
Hitchhiking Mapping Reveals a Candidate Genomic Region for Natural Selection in Three-Spined Stickleback Chromosome VIII
ABSTRACTIdentification of genes and genomic regions under directional natural selection has become one of the major goals in evolutionary genetics, but relatively little work to this end has been done by applying hitchhiking mapping to wild populations....
Human Fertility Increases with Marital Radius
ABSTRACTWe report a positive association between marital radius (distance between mates' birthplaces) and fertility detected in a large population. Spurious association due to socioeconomic factors is discarded by a conditional analysis involving income,...
Identification of Novel Activation Mechanisms for FLO11 Regulation in Saccharomyces Cerevisiae
ABSTRACTAdhesins play a central role in the cellular response of eukaryotic microorganisms to their host environment. In pathogens such as Candida spp. and other fungi, adhesins are responsible for adherence to mammalian tissues, and in Saccharomyces...
Identification of the Minus-Dominance Gene Ortholog in the Mating-Type Locus of Gonium Pectorale
ABSTRACTThe evolution of anisogamy/oogamy in the colonial Volvocales might have occurred in an ancestral isogamous colonial organism like Gonium pectorale. The unicellular, close relative Chlamydomonas reinhardtii has a mating-type (MT) locus harboring...
Inhibition of Transcription by the Caenorhabditis Elegans Germline Protein PIE-1: Genetic Evidence for Distinct Mechanisms Targeting Initiation and Elongation
ABSTRACTIn Caenorhabditis elegans embryos, specification of the germ lineage depends on PIE-1, a maternal protein that blocks mRNA transcription in germline blastomeres. Studies in mammalian cell culture have suggested that PIE-1 inhibits P-TEFb, a kinase...
Integrating Phylogenetic and Population Genetic Analyses of Multiple Loci to Test Species Divergence Hypotheses in Passerina Buntings
Phylogenetic and population genetic analyses of DNA sequence data from 10 nuclear loci were used to test species divergence hypotheses within Passerina buntings, with special focus on a strongly supported, but controversial, sister relationship between...
Investigations of CHD1 Function in Transcription and Development of Drosophila Melanogaster
ABSTRACTIn this report we describe chd1 mutant alleles and show that the CHD1 chromatin-remodeling factor is important for wing development and fertility. While CHD1 colocalizes with elongating RNA polymerase II (Pol II) on polytene chromosomes, elongating...
Loss of LINE-1 Activity in the Megabats
ABSTRACTLINE-1 (L1) retrotransposons are the most abundant type of mammalian retroelement. They have profound effects on genome plasticity and have been proposed to fulfill essential host functions, yet it remains unclear where they lie on the spectrum...
MEG-1 and MEG-2 Are Embryo-Specific P-Granule Components Required for Germline Development in Caenorhabditis Elegans
ABSTRACTIn Caenorhabditis elegans, germ granules called P granules are directly inherited from mother to daughter and segregate with the germ lineage as it separates from the soma during initial embryonic cell divisions. Here we define meg-1 and meg-2...
Mitochondrial DNA Transfer to the Nucleus Generates Extensive Insertion Site Variation in Maize
ABSTRACTMitochondrial DNA (mtDNA) insertions into nuclear chromosomes have been documented in a number of eukaryotes. We used fluorescence in situ hybridization (FISH) to examine the variation of mtDNA insertions in maize. Twenty overlapping cosmids,...
Molecular Population Genetics of Drosophila Subtelomeric DNA
ABSTRACTDNA sequence surveys in yeast and humans suggest that the forces shaping telomeric polymorphism and divergence are distinctly more dynamic than those in the euchromatic, gene-rich regions of the chromosomes. However, the generality of this pattern...
Naive Application of Permutation Testing Leads to Inflated Type I Error Rates
ABSTRACTFailure to account for family structure within populations or in complex mating designs via uninformed applications of permutation testing will lead to inflated type I error rates. Careful consideration of the design factors is essential since...
Novel X-Type High-Molecular-Weight Glutenin Genes from Aegilops Tauschii and Their Implications on the Wheat Origin and Evolution Mechanism of Glu-D1-1 Proteins
ABSTRACTTwo new x-type high-molecular-weight glutenin subunits with similar size to 1Dx5, designated 1Dx5*^sup t^ and 1Dx5.1*^sup t^ in Aegilops tauschii, were identified by SDS-PAGE, RP-HPLC, and MALDI-TOF-MS. The coding sequences were isolated by AS-PCR...
Parental Effect of DNA (Cytosine-5) Methyltransferase 1 on Grandparental-Origin-Dependent Transmission Ratio Distortion in Mouse Crosses and Human Families
ABSTRACTTransmission ratio distortion (TRD) is a deviation from the expected Mendelian 1:1 ratio of alleles transmitted from parents to offspring and may arise by different mechanisms. Earlier we described a grandparental-origin-dependent sex-of-offspring-specific...
Population Genetics of Polymorphism and Divergence under Fluctuating Selection
ABSTRACTCurrent methods for detecting fluctuating selection require time series data on genotype frequencies. Here, we propose an alternative approach that makes use of DNA polymorphism data from a sample of individuals collected at a single point in...
Population Genetics of Speciation in Two Closely Related Wild Tomatoes (Solanum Section Lycopersicon)
ABSTRACTWe present a multilocus sequencing study to assess patterns of polymorphism and divergence in the closely related wild tomato species, Solanum peruvianum and S. chilense (Solanum section Lycopersicon, Solanaceae). The data set comprises seven...
Precision of Recombination Frequency Estimates after Random Intermating with Finite Population Sizes
ABSTRACTRandom intermating of F^sub 2^ populations has been suggested for obtaining precise estimates of recombination frequencies between tightly linked loci. In a simulation study, sampling effects due to small population sizes in the intermating generations...
Quantitative Trait Loci for Grain Yield and Adaptation of Durum Wheat (Triticum Durum Desf.) across a Wide Range of Water Availability
ABSTRACTGrain yield is a major goal for the improvement of durum wheat, particularly in drought-prone areas. In this study, the genetic basis of grain yield (GY), heading date (HD), and plant height (PH) was investigated in a durum wheat population of...
Regulation of Serotonin Biosynthesis by the G Proteins G[alpha]^sub O^ and G[alpha]^sub Q^ Controls Serotonin Signaling in Caenorhabditis Elegans
ABSTRACTTo analyze mechanisms that modulate serotonin signaling, we investigated how Caenorhabditis elegans regulates the function of serotonergic motor neurons that stimulate egg-laying behavior. Egg laying is inhibited by the G protein Ga^sub o^ and...
Role of RAD51 in the Repair of MuDR-Induced Double-Strand Breaks in Maize (Zea Mays L.)
ABSTRACTRates of Mu transposon insertions and excisions are both high in late somatic cells of maize. In contrast, although high rates of insertions are observed in germinal cells, germinal excisions are recovered only rarely. Plants doubly homozygous...
Role of the Saccharomyces Cerevisiae Rad51 Paralogs in Sister Chromatid Recombination
ABSTRACTRad51 requires a number of other proteins, including the Rad51 paralogs, for efficient recombination in vivo. Current evidence suggests that the yeast Rad51 paralogs, Rad55 and Rad57, are important in formation or stabilization of the Rad51 nucleoprotein...
Rosy Function Is Required for Juvenile Hormone Effects in Drosophila Melanogaster
ABSTRACTApplication of a high dose of juvenile hormone (JH) III or its mimics (JHM) to Drosophila at the white puparium stage causes the formation of a pupal-like abdomen with few or no short bristles. We report here that the rosy (ry) gene encoding...
Salad Days in the Rhythms Trade
ONE of the nicest things anyone ever said about our workwas ina(necessarily) anonymous grant review fromthe early 1990s inwhich the author commented that our lab had contributed greatly to moving the study of circadian rhythms "out of the era of spoon-bending."...
Spatial and Temporal Control of Gene Expression in Drosophila Using the Inducible GeneSwitch GAL4 System. I. Screen for Larval Nervous System Drivers
ABSTRACTThere is a critical need for genetic methods for the inducible expression of transgenes in specific cells during development. A promising approach for this is the GeneSwitch GAL4 system of Drosophila. With GeneSwitch GAL4 the expression of upstream...
Testing for Archaic Hominin Admixture on the X Chromosome: Model Likelihoods for the Modern Human RRM2P4 Region from Summaries of Genealogical Topology under the Structured Coalescent
ABSTRACTA 2.4-kb stretch within the RRM2P4 region of the X chromosome, previously sequenced in a sample of 41 globally distributed humans, displayed both an ancient time to the most recent common ancestor (e.g., a TMRCA of ~2 million years) and a basal...
The Fixation of Locally Beneficial Alleles in a Metapopulation
ABSTRACTExtinction, recolonization, and local adaption are common in natural spatially structured populations. Understanding their effect upon genetic variation is important for systems such as genetically modified organism management or avoidance of...
The Telotype Defines the Telomere State in Saccharomyces Cerevisiae and Is Inherited as a Dominant Non-Mendelian Characteristic in Cells Lacking Telomerase
ABSTRACTTelomeres are an unusual component of the genome because they do not encode genes, but their structure and cellular maintenance machinery (which we define as "telotype") are essential for chromosome stability. Cells can switch between different...