scholarly journals Can Unlikely Neanderthal Chloride Channel CLC-2 Gene Variants Provide Insights in Modern Human Infertility?

2021 ◽  
Vol 55 (3) ◽  
pp. 301-310

Background/Aims: Neanderthals, although well adapted to local environments, were rapidly replaced by anatomically modern humans (AMH) for unknown reasons. Genetic information on Neanderthals is limited restricting applicability of standard population genetics. Methods: Here, we apply a novel combination of restricted genetic analyses on preselected physiological key players (ion channels), electrophysiological analyses of gene variants of unclear significance expressed in Xenopus laevis oocytes using two electrode voltage clamp and transfer of results to AMH genetics. Using genetic screening in infertile men identified a loss of CLC-2 associated with sperm deficiency. Results: Increased genetic variation caused functionally impaired Neanderthals CLC-2 channels. Conclusion: Increased genetic variation could reflect an adaptation to different local salt supplies at the cost of reduced sperm density. Interestingly and consistent with this hypothesis, lack of CLC-2 protein in a patient associates with high blood K+ concentration and azoospermia.

2003 ◽  
Vol 13 (2) ◽  
pp. 263-279 ◽  
Author(s):  
David Lewis-Williams ◽  
E. Thomas Lawson ◽  
Knut Helskog ◽  
David S. Whitley ◽  
Paul Mellars

David Lewis-Williams is well-known in rock-art circles as the author of a series of articles drawing on ethnographic material and shamanism (notably connected with the San rock art of southern Africa) to gain new insights into the Palaeolithic cave art of western Europe. Some 15 years ago, with Thomas Dowson, he proposed that Palaeolithic art owed its inspiration at least in part to trance experiences (altered states of consciousness) associated with shamanistic practices. Since that article appeared, the shamanistic hypothesis has both been widely adopted and developed in the study of different rock-art traditions, and has become the subject of lively and sometimes heated controversy. In the present volume, Lewis-Williams takes the argument further, and combines the shamanistic hypothesis with an interpretation of the development of human consciousness. He thus enters another contentious area of archaeological debate, seeking to understand west European cave art in the context of (and as a marker of) the new intellectual capacities of anatomically modern humans. Radiocarbon dates for the earliest west European cave art now place it contemporary with the demise of the Neanderthals around 30,000 years ago, and cave art, along with carved or decorated portable items, appears to announce the arrival and denote the success of modern humans in this region. Lewis-Williams argues that such cave art would have been beyond the capabilities of Neanderthals, and that this kind of artistic ability is unique to anatomically modern humans. Furthermore, he concludes that the development of the new ability cannot have been the product of hundreds of thousands of years of gradual hominid evolution, but must have arisen much more abruptly, within the novel neurological structure of anatomically modern humans. The Mind in the Cave is thus the product of two hypotheses, both of them contentious — the shamanistic interpretation of west European Upper Palaeolithic cave art, and the cognitive separation of modern humans and Neanderthals. But is it as simple as that? Was cave art the hallmark of a new cognitive ability and social consciousness that were beyond the reach of previous hominids? And is shamanism an outgrowth of the hard-wired structure of the modern human brain? We begin this Review Feature with a brief summary by David Lewis-Williams of the book's principal arguments. There follows a series of comments addressing both the meaning of the west European cave art, and its wider relevance for the understanding of the Neanderthal/modern human transition.


2018 ◽  
Vol 19 (12) ◽  
pp. 3879 ◽  
Author(s):  
Yi-Chun Chen ◽  
Kuo-Hsuan Chang ◽  
Chiung-Mei Chen

Differences in the incidence of spontaneous intracerebral hemorrhage (ICH) between ethnicities exist, with an estimated 42% of the variance explained by ethnicity itself. Caucasians have a higher proportion of lobar ICH (LICH, 15.4% of all ICH) than do Asians (3.4%). Alterations in the causal factor exposure between countries justify part of the ethnic variance in ICH incidence. One third of ICH risk can be explained by genetic variation; therefore, genetic differences between populations can partly explain the difference in ICH incidence. In this paper, we review the current knowledge of genetic variants associated with ICH in multiple ethnicities. Candidate gene variants reportedly associated with ICH were involved in the potential pathways of hypertension, vessel wall integrity, lipid metabolism, endothelial dysfunction, inflammation, platelet function, and coagulopathy. Furthermore, variations in APOE (in multiple ethnicities), PMF1/SLC25A44 (in European), ACE (in Asian), MTHFR (in multiple ethnicities), TRHDE (in European), and COL4A2 (in European) were the most convincingly associated with ICH. The majority of the associated genes provide small contributions to ICH risk, with few of them being replicated in multiple ethnicities.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Michael D. Gregory ◽  
J. Shane Kippenhan ◽  
Daniel P. Eisenberg ◽  
Philip D. Kohn ◽  
Dwight Dickinson ◽  
...  

2020 ◽  
Vol 12 (3) ◽  
pp. 189-200
Author(s):  
Anna Meiliana ◽  
Andi Wijaya

BACKGROUND: Since our conception to death, we were permanently exposed to nutrition. Indeed, food intake is the key of the environmental factor that modulates our gene. Nutrigenomics focus on how common dietary chemicals altering an individual’s genetic makeup including genome, proteome, and metabolome. While nutrigenetics refer to how the genetic variation gives different responses to nutrients.CONTENT: Nutrigenomics applied the high-throughput genomic-related tools to find out the influence of nutrients on the genes’ expression. While nutrigenetics (nutritional genetics) focus on the heterogenous response of gene variants to nutrients and dietary factors. Application nutrigenomics and nutrigenetics, integrated with system biology result in a precision nutrition as a relevant precise personal dietary change recommendation, thus will increase the motivation and sustain to whom the intervention is being delivered.SUMMARY: Individual diet recommendation is not simple. Many factors and tools should be involved adequately. The application of integrated -omics approaches, together with nutrigenomic and nutrigenetics for novel biomarker discovering and precision nutrition tailoring were expected to develop a healthier lifestyle and behavior.KEYWORDS: nutrigenetics, nutrigenomics, precision nutrition, metabolomics, system biology


2020 ◽  
Author(s):  
Courtney R. Garrison ◽  
Scott K. Sakaluk ◽  
Ned A. Dochtermann

AbstractIn many species, males produce signals to attract females. However, in some species and populations, only some males produce these signals with other males competing for and “sneaking” reproductive opportunities. In these systems, at least three tactics are expected: always signal, signal only when others are not (assessors), and never signal. The representation of these tactics within a population is unknown in part because the costs of signaling (C) and the fitness value of a single reproductive bout (V) are unknown. Using a game-theoretic model we predict that the always signal strategy only persists if the fitness value of calling is greater than twice the cost. We also show that always signal males are apparently absent in decorated crickets (Gryllodes sigillatus). Moreover, males of this species were not strict assessors and instead signaled infrequently (30% of the time) when signaling by others was constant. Males also exhibited substantial among-individual variation in the propensity to call when other males were not signaling (τ = 0.3). Our results suggest a high relative cost of signaling (2C > V) in this species. The presence of among-individual variation is indicative of underlying genetic variation and a mixed evolutionary stable strategy.


Author(s):  
Philip J. White ◽  
Michael J. Bell ◽  
Ivica Djalovic ◽  
Philippe Hinsinger ◽  
Zed Rengel

AbstractThere are many terms used to define aspects of potassium (K) use efficiency of plants. The terms used most frequently in an agricultural context are (1) agronomic K use efficiency (KUE), which is defined as yield per unit K available to a crop and is numerically equal to the product of (2) the K uptake efficiency (KUpE) of the crop, which is defined as crop K content per unit K available and (3) its K utilization efficiency (KUtE), which is defined as yield per unit crop K content. There is considerable genetic variation between and within plant species in KUE, KUpE, and KUtE. Root systems of genotypes with greatest KUpE often have an ability (1) to exploit the soil volume effectively, (2) to manipulate the rhizosphere to release nonexchangeable K from soil, and (3) to take up K at low rhizosphere K concentrations. Genotypes with greatest KUtE have the ability (1) to redistribute K from older to younger tissues to maintain growth and photosynthesis and (2) to reduce vacuolar K concentration, while maintaining an appropriate K concentration in metabolically active subcellular compartments, either by anatomical adaptation or by greater substitution of K with other solutes in the vacuole. Genetic variation in traits related to KUpE and KUtE might be exploited in breeding crop genotypes that require less K fertilizer. This could reduce fertilizer costs, protect the environment, and slow the exhaustion of nonrenewable resources.


Author(s):  
Andrew P. Hendry

This chapter outlines how to conceptualize and predict adaptive evolution based on information about selection and genetic variation. It introduces and explains adaptive landscapes, a concept that has proven useful in guiding the understanding of evolution. The chapter also reviews empirical data to answer fundamental questions about adaptation in nature, including to what extent short- and long-term evolution is predictable, how fast is phenotypic change, to what extent is adaptation constrained by genetic variation, and how well adapted natural populations are to their local environments. Moving beyond selection and adaptation within populations, the chapter shows how eco-evolutionary dynamics will be shaped by biological diversity: that is, different populations and species have different effects on their environment.


2020 ◽  
Author(s):  
Elena Skosey-LaLonde ◽  
Ana Gomes ◽  
Maria João Martins ◽  
Simon Connor ◽  
Mussa Raja ◽  
...  

<p>In order to better quantify the role of climate variability in southeastern Africa, and its impact on the evolution and spread of anatomically modern humans, our international and interdisciplinary team cored a series of coastal lakes during the summer of 2019. Here, we present data from lake Nyalonzelwe, one of many interdunal lakes present along the coast in the Inhambane region of southeastern Mozambique. Nyalonzelwe sits 5m above MSL and is bounded by a Pleistocene dune system, reaching between 29-121m in elevation, protecting the lake from the Indian Ocean. The sedimentological record of Nyalonzelwe presents over 6m of stratigraphic variability, including a varve sequence spanning the basal 2m, making it an incredibly rare record of seasonal resolution climate variability and the first record of its kind in Mozambique. Two cores, C1 and C4, with depths of 6.12m and 6.22m respectively, were collected for multiproxy biogeochemical analyses and C<sup>14</sup> dating using a Livingstone corer. This work seeks to present the results of Carbon, Hydrogen, Nitrogen (CHN) elemental analysis for core C1, sampled at 10 cm intervals and aragonite/calcite ratios for gastropod assemblages across C4, sampled at 1 cm resolution in preparation for stable isotope analysis.</p><p>CHN analysis was conducted using an Elementar model Vario EL III at the University of Algarve CCMAR for both organic and inorganic carbon present in sediment samples from C1. Aragonite/calcite ratios for identified gastropod species, namely <em>Melanoides tuberculata</em>, were collected from individual representatives in samples from C4 with more than 8 individuals present and determined using Fourier Transform Infrared Spectroscopy at the University of Connecticut. Nyalonzelwe cores C1 and C4 are stratigraphically correlated. Together these data represent the first look at Quaternary paleoenvironmental evolution in southeastern coastal Mozambique and the importance of climate (in)stability in the region and its impact on early modern human populations. This work was supported by the project PTDC/HAR-ARQ/28148/2017, funded by the Portuguese Foundation for Science and Technology.</p>


1969 ◽  
Vol 47 (7) ◽  
pp. 1081-1084 ◽  
Author(s):  
A. H. Teich ◽  
M. J. Holst

A Scots pine clone bearing cone clusters transmitted precocity to a portion of its progeny resulting from crosses to clones having normal cone distribution. Inheritance appeared to be governed by a single major gene whose expression was dominant or recessive depending upon which clone it was mated to. Differences of reciprocal crosses indicated maternal or cytoplasmic influence. This genetic variation in precocity can be used to reduce the generation interval, thereby facilitating genetic studies and breeding programs. Seed yield per pollination bag was several times greater for cone clusters than for normally distributed cones although viable seed per cone was 20% less. This can reduce the cost of producing hybrid seed if artificial pollination is required.


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