Centralizing content and distributing labor: a community model for curating the very long tail of microbial genomes.

Centralizing content and distributing labor: a community model for curating the very long tail of microbial genomes.

Tim Putman, Sebastian Burgstaller, Andra Waagmeester, Chunlei Wu, Andrew I Su, Benjamin Good

Surprisingly weak coordination between leaf structure and function among closely-related tomato species

Surprisingly weak coordination between leaf structure and function among closely-related tomato species

Christopher D Muir, Miquel Ángel Conesa, Emilio Roldán, Arántzazu Molins, Jeroni Galmés

Scan-o-matic: high-resolution microbial phenomics at a massive scale

Scan-o-matic: high-resolution microbial phenomics at a massive scale

Martin Zackrisson, Johan Hallin, Lars-Göran Ottosson, Peter Dahl, Esteban Fernandez-Parada, Erik Ländström, Luciano Fernandez-Ricaud, Petra Kaferle, Andreas Skyman, Stig Omholt, Uros Petrovic, Jonas Warringer, Anders Blomberg

Are all global alignment algorithms and implementations correct?

Are all global alignment algorithms and implementations correct?

Tomáš Flouri, Kassian Kobert, Torbjørn Rognes, Alexandros Stamatakis

Characterization of expression quantitative trait loci in extensively phenotyped pedigrees ascertained for bipolar disorder

Characterization of expression quantitative trait loci in extensively phenotyped pedigrees ascertained for bipolar disorder

Christine Peterson, Susan Service, Anna Jasinska, Fuying Gao, Ivette Zelaya, Terri Teshiba, Carrie Bearden, Victor Reus, Gabriel Macaya, Carlos López-Jaramillo, Marina Bogomolov, Yoav Benjamini, Eleazar Eskin, Giovanni Coppola, Nelson Freimer, Chiara Sabatti

Human knockouts in a cohort with a high rate of consanguinity

Human knockouts in a cohort with a high rate of consanguinity

Danesh Saleheen, Pradeep Natarajan, Wei Zhao, Asif Rasheed, Sumeet Khetarpal, Hong-Hee Won, Konrad J Karczewski, Anne H ODonnell-Luria, Kaitlin E Samocha, Namrata Gupta, Mozzam Zaidi, Maria Samuel, Atif Imran, Shahid Abbas, Faisal Majeed, Madiha Ishaq, Saba Akhtar, Kevin Trindade, Megan Mucksavage, Nadeem Qamar, Khan S Zaman, Zia Yaqoob, Tahir Saghir, Syed NH Rizvi, Anis Memon, Nadeem H Mallick, Mohammad Ishaq, Syed Z Rasheed, Fazal ur Rehman Memon, Khalid Mahmood, Naveeduddin Ahmed, Ron Do, Daniel G MacArthur, Stacey Gabriel, Eric S Lander, Mark J Daly, Philippe Frossard, John Danesh, Daniel J Rader, Sekar Kathiresan

A major goal of biomedicine is to understand the function of every gene in the human genome. Null mutations can disrupt both copies of a given gene in humans and phenotypic analysis of such ‘human knockouts’ can provide insight into gene function. To date, comprehensive analysis of genes knocked out in humans has been limited by the fact that null mutations are infrequent in the general population and so, observing an individual homozygous null for a given gene is exceedingly rare. However, consanguineous unions are more likely to result in offspring who carry homozygous null mutations. In Pakistan, consanguinity rates are notably high. Here, we sequenced the protein-coding regions of 7,078 adult participants living in Pakistan and performed phenotypic analysis to identify homozygous null individuals and to understand consequences of complete gene disruption in humans. We enumerated 36,850 rare (<1 % minor allele frequency) null mutations. These homozygous null mutations led to complete inactivation of 961 genes in at least one participant. Homozygosity for null mutations at APOC3 was associated with absent plasma apolipoprotein C-III levels; at PLAG27, with absent enzymatic activity of soluble lipoprotein-associated phospholipase A2; at CYP2F1, with higher plasma interleukin-8 concentrations; and at either A3GALT2 or NRG4, with markedly reduced plasma insulin C-peptide concentrations. After physiologic challenge with oral fat, APOC3 knockouts displayed marked blunting of the usual post-prandial rise in plasma triglycerides compared to wild-type family members. These observations provide a roadmap to understand the consequences of complete disruption of a large fraction of genes in the human genome.

Rising out of the ashes: additive genetic variation for susceptibility to Hymenoscyphus fraxineus in Fraxinus excelsior

Facundo Muñoz, Benoit Marçais, Jean Dufour, Arnaud Dowkiw

Environmental unpredictability and inbreeding depression select for mixed dispersal syndromes

Environmental unpredictability and inbreeding depression select for mixed dispersal syndromes
Jorge Hidalgo, Rafael Rubio de Casas, Miguel A. Munoz

Mixed dispersal syndromes have historically been regarded as bet-hedging mechanisms that enhance survival in unpredictable environments, ensuring that some propagules stay in the maternal environment while others can potentially colonize new sites. However, this entails paying the costs of both dispersal and non-dispersal. Propagules that disperse are likely to encounter unfavorable conditions for establishment, while non-dispersing propagules might form populations of close relatives burdened with inbreeding. Here, we investigate the conditions under which mixed dispersal syndromes emerge and are evolutionarily stable, taking into account the risks of both environmental unpredictability and inbreeding. Using mathematical and computational modeling we show that high dispersal propensity is favored whenever temporal environmental unpredictability is low and inbreeding depression high, whereas mixed dispersal syndromes are adaptive under conditions of high environmental unpredictability, but more particularly if also inbreeding depression is small. Although pure dispersers can be selected for under some circumstances, mixed dispersal provides the optimal strategy under most parameterizations of our models, indicating that this strategy is likely to be favored under a wide variety of conditions. Furthermore, populations exhibiting any single phenotype go inevitably extinct when environmental and genetic costs are high, whilst mixed strategies can maintain viable populations even under such conditions. Our models support the hypothesis that the interplay between inbreeding depression and environmental unpredictability shapes dispersal syndromes, often resulting in mixed strategies. Moreover, mixed dispersal seems to facilitate persistence whenever conditions are critical or nearly critical for survival.

Toy model for the adaptive origins of the sexual orientation continuum

Toy model for the adaptive origins of the sexual orientation continuum
Brian Skinner

Same-sex sexual behavior is ubiquitous in the animal kingdom, but its adaptive origins remain a prominent puzzle. Here I suggest the possibility that same-sex sexual behavior arises as a consequence of the competition between an evolutionary drive for a wide diversity in traits, which improves the adaptability of a species, and a drive for sexual dichotomization of traits, which promotes opposite-sex attraction and increases the rate of reproduction. A simple analytical “toy model” is proposed for describing this tradeoff. The model exhibits a number of interesting features, and suggests a simple mathematical form for describing the sexual orientation continuum.

Automatic and accurate identification of integrons and cassette arrays in bacterial genomes reveals unexpected patterns

Automatic and accurate identification of integrons and cassette arrays in bacterial genomes reveals unexpected patterns

Jean Cury, Thomas Jové, Marie Touchon, Bertrand Néron, Eduardo PC Rocha