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Quantitative genetics aims at untangling the genetic and environmental effects on phenotypic variation. Trait heritability, which summarizes the relative importance of genetic effects, is estimated at the intraspecific level, but theory predicts that heritability could influence long-term evolution of quantitative traits. The phylogenetic signal concept bears resemblance to heritability and it has often been called species-level heritability. Under certain conditions, such as trait neutrality or contribution to phylogenesis, within-species heritability and between-species phylogenetic signal should be correlated. Here, we investigate the potential relationship between these two concepts by examining the evolution of multiple morphological traits for which heritability has been estimated in Drosophila melanogaster. Specifically, we analysed 42 morphological traits in both sexes on a phylogeny inferred from 22 nuclear genes for nine species of the melanogaster subgroup. We used Pagel's λ as a measurement of phylogenetic signal because it is the least influenced by the number of analysed taxa. Pigmentation traits showed the strongest concordance with the phylogeny, but no correlation was found between phylogenetic signal and heritability estimates mined from the literature. We obtained data for multiple climatic variables inferred from the geographical distribution of each species. Phylogenetic regression of quantitative traits on climatic variables showed a significantly positive correlation with heritability. Convergent selection, the response to which depends on the trait heritability, may have led to the null association between phylogenetic signal and heritability for morphological traits in Drosophila. We discuss the possible causes of discrepancy between both statistics and caution against their confusion in evolutionary biology.

Tanytarsini is a large tribe of Chironomidae with at least 11 recorded marine species grouped in three genera. In this study, we performed a phylogenic analysis using molecular data from 13 Tanytarsini genera, including all Japanese marine species in a large tribe of Chironominae, to estimate their phylogenetic positions and evolutionary history. The phylogenetic reconstruction grouped the marine species in two clades. One clade was composed of five marine Tanytarsus and two marine Pontomyia species within a larger clade of Tanytarsus. Pontomyia is considered to have morphologically specialized and adapted to marine environments by rapid evolution, although it formed a clade with Tanytarsus. The only one species of Tanytarsus, T. pelagicus, clustered as a member of the second clade, which was mainly composed by species of the genus Paratanytarsus. Thus, we redescribe T. pelagicus as Paratanytarsus pelagicus.

Rice is highly vulnerable to salt stress at both seedling and flowering stage. While research efforts largely focused on seedling stage salinity tolerance, flowering stage salt tolerance studies are limited. Development of rice cultivars with salt tolerance at both stages will enhance rice productivity in salt affected farmlands. In the present study, two introgression line (IL) populations of a salt-tolerant landrace 'Nona Bokra (N)' were developed in the genetic backgrounds of two U.S. cultivars 'Cheniere (C)' and 'Jupiter (J)' and were evaluated for elucidation of the genetic basis of agronomically important traits at flowering stage and development of salt tolerant pre-breeding lines. Evaluation of both sets of ILs (JN-ILs and CN-ILs) under saline (EC = 8 dSm^-1) environment led to identification of a total of 33 QTLs for seven different yield and yield component traits impacted by salt stress. Majority of large-effect QTLs for traits such as panicle length (qPL1.1^JN), spikelet sterility (qSS1.1^JN), thousand-grain weight (qTGW1.1^JN), days to flowering (qDFF1.1^CN), and plant height (qPH1.1^CN) were located on chromosome 1. Some candidate genes present within the major effect QTL regions include potassium channel OsKAT1, NAC domain-containing protein, potassium transporters, and photosensitive leaf rolling 1. Comparison of the results with earlier reports on seedling stage suggested a different set of genes controlling salt tolerance at both stages. In addition, pre-breeding lines with improved flowering stage salinity tolerance were identified. These pre-breeding rice lines will accelerate fine mapping, map-based cloning, and pyramiding of desirable alleles for both flowering and seedling stage salt tolerance through marker assisted selection.

Correctly delimiting species and populations is a prerequisite for studies of connectivity, adaptation and conservation. Genomic data are particularly useful to test species differentiation for organisms with few informative morphological characters or low discrimination of cytoplasmic markers, as in Scleractinians. Here we applied Restriction site Associated DNA sequencing (RAD-sequencing) to the study of species differentiation and genetic structure in populations of Pocillopora spp. from Oman and French Polynesia, with the objectives to test species hypotheses, and to study the genetic structure among sampling sites within species. We focused here on coral colonies morphologically similar to P. acuta (damicornis type β). We tested the impact of different filtering strategies on the stability of the results. The main genetic differentiation was observed between samples from Oman and French Polynesia. These samples corresponded to different previously defined primary species hypotheses (PSH), i.e., PSHs 12 and 13 in Oman, and PSH 5 in French Polynesia. In Oman, we did not observe any clear differentiation between the two putative species PSH 12 and 13, nor between sampling sites. In French Polynesia, where a single species hypothesis was studied, there was no differentiation between sites. Our analyses allowed the identification of clonal lineages in Oman and French Polynesia. The impact of clonality on genetic diversity is discussed in light of individual-based simulations.

Although predicting the effects of variants near intron-exon boundaries is relatively straightforward, predicting the functional Exon Splicing Enhancers (ESEs) and the possible effects of variants within ESEs remains a challenge. Considering the essential role of CYP2D6/CYP2C19 genes in drug metabolism, we attempted to identify variants that are most likely to disrupt splicing through their effect on these ESEs. ESEs were predicted in these two genes using ESEfinder 3.0, incorporating a series of filters (increased threshold and evolutionary conservation). Finally, reported mutations were evaluated for their potential to disrupt splicing by affecting these ESEs. Initially, 169 and 243 ESEs were predicted for CYP2C19/CYP2D6, respectively. However, applying the filters, the number of predicted ESEs was reduced to 26 and 19 in CYP2C19/CYP2D6, respectively. Comparing prioritized predicted ESEs with known sequence variants in CYP2C19/CYP2D6 genes highlights 18 variations within conserved ESEs for each gene. We found good agreement in cases where such predictions could be compared to experimental evidence. In total, we prioritized a subset of mutational changes in CYP2C19/CYP2D6 genes that may affect the function of these genes and lead to altered drug responses. Clinical studies and functional analysis for investigating detailed functional consequences of the mentioned mutations and their phenotypic outcomes is mostly recommended.

The complete mitogenome sequence of Talpa martinorum, a recently described Balkan endemic mole, was assembled from next generation sequence data. The mitogenome is similar to that of the three other Talpa species sequenced to date, being 16,835 bp in length, and containing 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, an origin of L-strand replication, and a control region or D-loop. Compared to other Talpa mitogenomes sequenced to date, that of T. martinorum differs in the length of D-loop and stop codon usage. TAG and T-- are the stop codons for the ND1 and ATP8 genes, respectively, in T. martinorum, whilst TAA acts as a stop codon for both ND1 and ATP8 in the other three Talpa species sequenced. Phylogeny reconstructions based on Maximum Likelihood and Bayesian inference analyses yielded phylogenies with similar topologies, demonstrating that T. martinorum nests within the western lineage of the genus, being closely related to T. aquitania and T. occidentalis.

Epimutations and mutations are two dissimilar mechanisms that have contributed to the phenotypic diversities in organisms. Though dissimilar, many previous studies have revealed that the consequences of epimutations and mutations are not mutually exclusive. DNA rich in epigenetic modifications can be prone to mutations and vice versa. In order to get a better insight into the molecular evolution in organisms, it is important to consider the information of both genetic and epigenetic changes in their genomes. Understanding the similarities and differences between the consequences of epimutations and mutations is required for a better interpretation of phenotypic diversities in organisms. Factors contributing to epigenetic changes such as paramutations and mutation hotspots and, the correlation of the interdependence of mutations and epigenetic changes in DNA are important aspects that need to be considered for molecular evolutionary studies. Thus, this review explains what epimutations are, their causes, how they are similar/different from mutations, and the influence of epigenetic changes and mutations on each other, further emphasizing how molecular evolution involving both mutations and epimutations can lead to speciation. Considering this approach will aid in reorganizing taxonomic classifications, importantly, solving disparities in species identification.

Even though the word "phenotype", as well as the expression "genotype-phenotype relationship", are a part of the everyday language of biologists, they remain abstract notions that are sometimes misunderstood or misused. In this article, I begin with a review of  the genesis of the concept of phenotype and of the meaning of the genotype-phenotype "relationship" from a historical perspective. I then illustrate how the development of new approaches for exploring the living world has enabled us to phenotype organisms at multiple levels, with traits that can either be measures or parameters of functions, leading to a virtually unlimited amount of phenotypic data. Thus, pleiotropy becomes a central issue in the study of the genotype-phenotype relationship. Finally, I provide a few examples showing that important genetic and evolutionary features clearly differ with the phenotypic level considered. The way genotypic variation propagates across the phenotypic levels to shape fitness variation is an essential research program in biology.

In this paper, we explain the concept of heritability and describe the different methods and the genotype-phenotype correspondences used to estimate heritability in the specific field of human genetics. Heritability studies are conducted on extremely diverse human traits: quantitative traits (physical, biological, but also cognitive and behavioral measurements) and binary traits (as is the case of most human diseases). Instead of variables such as education and socio-economic status as covariates in genetic studies, they are now the direct object of genetic analysis. We make a review of the different assumptions underlying heritability estimates and dispute the validity of most of them. Moreover, and maybe more importantly, we show that they are very often misinterpreted. These erroneous interpretations lead to a vision of a genetic determinism of human traits. This vision is currently being widely disseminated not only by the mass media and the mainstream press, but also by the scientific press. We caution against the dangerous implication it has both medically and socially. Contrarily to the field of animal and plant genetics for which the polygenic model and the concept of heritability revolutionized selection methods, we explain why it does not provide answer in human genetics.