mutation – Page 3 – Shamskm: A site to exchange knowledge and solutions

UCLA Biologists Reveal Potential ‘Fatal Flaw’ In Iconic Sexual Selection Study

By Guest PostJune 27, 2012Scienceangus john bateman, charles darwin, common fruit fly, curly wings, descent of man, dna analysis, double mutant offspring, drosophila melanogaster, eastern bluebirds, english geneticist, evolutionary advantage, fatal flaw, female, female behavior, fruit flies, kim derose, male, mate, molecular genetics, mutation, paradigms, patricia adair gowaty, promiscuous, sexual selection, wyatt anderson, yong kyu kim

A classic study from more than 60 years ago suggesting that males are more promiscuous and females more choosy in selecting mates may, in fact, be wrong, say life scientists who are the first to repeat the historic experiment using the same methods as the original.

In 1948, English geneticist Angus John Bateman published a study showing that male fruit flies gain an evolutionary advantage from having multiple mates, while their female counterparts do not. Bateman’s conclusions have informed and influenced an entire sub-field of evolutionary biology for decades.

“Bateman’s 1948 study is the most-cited experimental paper in sexual selection today because of its conclusions about how the number of mates influences fitness in males and females,” said Patricia Adair Gowaty, a distinguished professor of ecology and evolutionary biology at UCLA. “Yet despite its important status, the experiment has never been repeated with the methods that Bateman himself originally used, until now. (more…)

Disease that Stunts Infants’ Growth Traced to Same Gene that Makes Kids Grow too Fast

By Guest PostMay 30, 2012Scienceabhik banerjee, acronym, adrenal hypoplasia, alice, alice fleming, beckwith wiedemann syndrome, caterpillar, children, chromosome 11, dna sample, edward mccabe, eric vilain, france, geneticist, genital anomalies, genome, growth restriction, hane lee, hormone replacement therapy, image syndrome, infants growth, john achermann, lewis carroll, metaphyseal dysplasia, mushroom, mutation, nature genetics, protein coding factory, ucla, valerie arboleda, wonderland

Discovery ends UCLA scientist’s 20-year quest for cause of IMAGe syndrome

The Caterpillar got down off the mushroom … remarking as it went, ‘One side will make you grow taller, and the other side will make you grow shorter.’

—Lewis Carroll, “Alice’s Adventures in Wonderland”

UCLA geneticists have identified the mutation responsible for IMAGe syndrome, a rare disorder that stunts infants’ growth. The twist? The mutation occurs on the same gene that causes Beckwith–Wiedemann syndrome, which makes cells grow too fast, leading to very large children.

Published in the May 27 edition of the journal Nature Genetics, the UCLA findings could lead to new ways of blocking the rapid cell division that allows tumors to grow unchecked. The discovery also offers a new tool for diagnosing children with IMAGe syndrome, which until now has been difficult to identify accurately. (more…)

Low Quality Genes May Cause Mutational Meltdown

By Guest PostApril 19, 2012Scienceaneil agrawal, chromosome, DNA, dna damage, drosophila melanogaster, eeb, environmental stress, evolutionary biologist, extinction, fruit fly, genetic deficiencies, high quality gene, low quality gene, mammal, mutation, nathaniel sharp, poor genetic quality, repairing dna, species, university of toronto

Deficiencies compound over time, researchers say

Evolutionary biologists at the University of Toronto have found that individuals with low-quality genes may produce offspring with even more inferior chromosomes, possibly leading to the extinction of certain species over generations.

Their study, published in Proceedings of the National Academy of Sciences, predicts that organisms with such genetic deficiencies could experience an increased number of mutations in their DNA, relative to individuals with high-quality genes. The research was done on fruit flies whose simple system replicates aspects of biology in more complex systems, so the findings could have implications for humans. (more…)

Cancer Genes Differ in Different Parts of a Tumour

By Guest PostMarch 17, 2012Health, Sciencebiomarkers, biopsies, biopsy, cancer cell, cancer treatment, charles swanton, gene faults, genetic fault, genetic landscape, genetic variation, genome, genome sequencing technology, james larkin, kidney cancer, kidney tumours, lesley walker, molecular change, mutation, primary tumour, subtype, theory, tree of life, tumour, ubiquitous mutations

Taking a sample from just one part of a tumour may not give a full picture of its‘genetic landscape’, according to a study published in the New England Journal of Medicine.

The findings could help explain why attempts at using single biopsies to identify biomarkers to which personalised cancer treatments can be targeted have not been more successful. (more…)

MSU Researchers Show How New Viruses Evolve, And in Some Cases, Become Deadly

By Guest PostJanuary 27, 2012Sciencebacteria, beacon, beneficial mutation, bird flu, devin dobias, e coli bacterium, evolve, jeff barrick, justin meyer, lambda, michigan state university, mutation, natural selection, Netherlands, new virus, ompf protein, ribbon diagram, richard lenski, ryan quick, Science, survival of the fittest, united states, virus evolution

EAST LANSING, Mich. — In the current issue of Science, researchers at Michigan State University demonstrate how a new virus evolves, which sheds light on how easy it can be for diseases to gain dangerous mutations.

The scientists showed for the first time how the virus called “Lambda” evolved to find a new way to attack host cells, an innovation that took four mutations to accomplish. This virus infects bacteria, in particular the common E. coli bacterium. Lambda isn’t dangerous to humans, but this research demonstrated how viruses evolve complex and potentially deadly new traits, said Justin Meyer, MSU graduate student, who co-authored the paper with Richard Lenski, MSU Hannah Distinguished Professor of Microbiology and Molecular Genetics. (more…)

Researchers Uncover How New Melanoma Drug Accelerates Secondary Skin Cancers

By Guest PostJanuary 20, 2012Healthantoni ribas, braf mutation, cancer growth, cancer mutation, cancer treatment, drug, hematology, malignant cells, mechanism, mek inhibitor, melanoma cells, metastatic melanoma, mutated braf protein, mutation, oncogenic mutations, oncology, patients, plexxikon, ras mutation, roche, ruby family foundation, seaver institute, secondary skin cancers, side effect, skin squamous cell carcinomas, vemurafenib, zelboraf

Patients with metastatic melanoma taking the recently approved drug vemurafenib (marketed as Zelboraf) responded well to the twice-daily pill, but some of them developed a different, secondary skin cancer.

Now, researchers at UCLA’s Jonsson Comprehensive Cancer Center, working with investigators from the Institute of Cancer Research in London, Roche and Plexxikon, have elucidated the mechanism by which the drug excels at fighting melanoma but also allows for the development of skin squamous-cell carcinomas. (more…)

Close Family Ties Keep Microbial Cheaters in Check, Study Finds

By Guest PostDecember 16, 2011Scienceamoebae, Antarctica, canopies, clonal lineage, cosmopolitan groups, david queller, deserts, dicty, dictyostelium discoideum, e coli, evolution, forest park, genes, jennie kuzdzal fick, joan strassmann, kissing kin, life cycles, multicellular organisms, mutation, national science foundation, obligate cheaters, sam scheiner, sara fox, single cell, slime mold, social amoeba, st. louis, tropical forests, washington university

*Experiments on “slime mold” explain why almost all multicellular organisms begin life as a single cell*

Any multicellular animal, from a blue whale to a human being, poses a special challenge for evolution.

Most of the cells in its body will die without reproducing; only a privileged few will pass their genes to the next generation.

How could the extreme degree of cooperation required by multicellular existence actually evolve? Why aren’t all creatures unicellular individualists determined to pass on their own genes? (more…)

WHOI Teaming with Flatley Discovery Lab in Search for Effective Treatments for Cystic Fibrosis

By Guest PostOctober 13, 2011Health, Scienceantibiotics, biological and chemical processes of ocean microbes, cf, cftr, cftr gene, charlestown, chemical extracts, cystic fibrosis, cystic fibrosis trans-membrane conductance regulator, flatley discovery lab, fungi, gene, john flatley, marine actinomycetes, marine microbes, marine microbial extracts, membrane, microbes, microbial infection biofilm, mutation, phytoplankton, respiratory disease, richard fitzpatrick, sodium transport, susan k. avery, therapeutic agents for cystic fibrosis, tracy mincer, whoi, woods hole oceanographic institution

The Woods Hole Oceanographic Institution (WHOI) has signed a $1.18 million agreement with the Flatley Discovery Lab in Charlestown, Mass., to investigate and supply marine microbial extracts as possible treatments for cystic fibrosis (CF).

The life-shortening respiratory disease has eluded attempts at a cure, although researchers have been successful in some cases at adding years to a person’s lifespan, primarily through treatment with antibiotics. (more…)

Tag Archives: mutation