Scientists crack difficult wheat genome

29 November 2012. Source: www.abc.net.au/science/articles/2012/11/29/3643435.htm?topic=tech&WT.svl=healthscience2

The genome of the bread wheat, whose DNA is notoriously complex, is close to being completed, according to an international team of scientists.

Publishing in the journal Nature, they say they had analysed between 94,000 and 96,000 genes in bread wheat (Triticum aestivum).

According to the paper, the plant’s genome is nearly five times as big as humans.

The genes exist in what is in fact a triple genome, reflecting bread wheat’s legacy as the 8000-year-old offspring of three species of grasses.

Gene sequencing will help plant breeders in their search for strains that offer higher yields and are better able to tolerate floods, droughts and salty soils, the researchers said.

Wheat today accounts for a fifth of the world’s calorific intake, and this importance can only grow, given the world’s rising population and the impact of climate change on food production, say experts.

“This work moves us one step closer to a comprehensive and highly detailed genome sequence for bread wheat, which along with rice and maize is one of the three pillars on which the global food supply rests,” says co-author Jan Dvorak, a professor of plant sciences at the University of California at Davis.

“The world’s population is projected to grow from seven to nine billion by 2050,” says Dvorak.

“It is clear that, with no new farmable land available to bring into cultivation, we must develop higher-yielding varieties of these three cereals to meet the growing global demand for food.”

A complete, “polished” version of the genome may still lie several years away, says Neil Hall of the University of Liverpool, England, which led the research.

Although the genome has not been fully decoded, we now have instrumentation that can read DNA hundreds of times faster than the system that were used to sequence the human genome,” which was published in 2001, he says.

SCIENTISTS CRACK PEAR’S GENOME

19 November 2012. Source: www.genomics.cn/en/news/show_news?nid=99287

Scientists from Nanjing Agricultural University, Beijing Genomics Institute (BGI), and other institutions reported in Genome Research journal, the completion of the first genetic sequence of the pear. The pear genome will help scientists produce better pear varieties. Comparative genomics and evolution studies using the pear’s genome led to the discovery that pear, apple, and strawberry shared an ancient whole-genome duplication event that occurred 140 million years ago. It is expected that more discoveries on the pear’s genetic evolution will be known now that the genome is completely sequenced.

The scientists used BAC-by-BAC strategy and advanced sequencing techniques to crack pear’s genome. According to Zhiwen Wang of BGI, thte BAC-by-BAC strategy is fit for genomes with high heterozygosity.

INT- SCIENTISTS CALL FOR RETRACTION

Science journal urged to retract Monsanto GM study

Source: Reuters.

http://news.yahoo.com/science-journal-urged-retract-monsanto-gm-study-183006302.html

LONDON (Reuters) – The publisher of a much-criticised study suggesting genetically modified corn caused tumours in rats has come under heavy pressure from scientists to retract the paper and explain why it was ever printed.

The calls follow a report by Europe’s food safety watchdog this week dismissing the study’s findings.

Reed Elsevier, which published the study in its Food and Chemical Toxicology journal in September, said on Friday it was considering the criticisms and would let readers know if it concluded it needed to change the way it checked research.

In a statement on its website, the journal said “the paper was published after being objectively and anonymously peer reviewed, with a series of revisions made by the authors and the corrected paper then accepted by the editor.”

Hundreds of scientists from around the world have questioned the research, which was written by French researcher Gilles-Eric Seralini of the University of Caen and said rats fed on Monsanto’s GM corn suffered tumours and multiple organ failure.

Genetically modified crops are deeply unpopular in Europe but are common in the United State where they have been grown and consumed for more than 15 years.

A day after the study was published, Seralini defended his work, saying it was the most detailed study on the subject to date.

But more than 700 scientists have signed an online petition calling on Seralini to release all the data from his research.

The petition, addressed directly to Seralini, says: “Only a full disclosure of the data can quell any uncertainties over the results you published.”

EU – SERALINI STUDY FLAWED: EFSA

Seralini et al. study conclusions not supported by data, says EU risk assessment community 28 November 2012. Source: www.efsa.europa.eu/en/press/news/121128.htm?utm_source=feed&utm_medium=rss&utm_campaign=prwns

Serious defects in the design and methodology of a paper by Séralini et al. mean it does not meet acceptable scientific standards and there is no need to re-examine previous safety evaluations of genetically modified maize NK603. These are the conclusions of separate and independent assessments carried out by the European Food Safety Authority (EFSA) and six EU Member States following publication of the paper in the journal Food and Chemical Toxicology on 19 September 2012.

EFSA today delivered its final evaluation of the paper by Séralini et al. which raised concerns about the potential toxicity of genetically modified (GM) maize NK603 and of a herbicide containing glyphosate. In particular, it suggested a link between exposure to these substances and an increased incidence of tumours in rats. The Authority’s final review reaffirmed its initial assessment that the authors’ conclusions cannot be regarded as scientifically sound because of inadequacies in the design, reporting and analysis of the study as outlined in the paper. Consequently, it is not possible to draw valid conclusions about the occurrence of tumours in the rats tested. Based on the information published by Séralini et al., EFSA finds there is no need to re-examine its previous safety evaluations of NK603 or to consider these findings in the ongoing assessment of glyphosate.

Per Bergman, who led EFSA’s work, said: “EFSA’s analysis has shown that deficiencies in the Séralini et al. paper mean it is of insufficient scientific quality for risk assessment. In addition, several national organisations were independently mandated by Member States to assess this study. These reviews have demonstrated a consensus among a significant part of the EU risk assessment community that the conclusions of Séralini et al. are not supported by the data in the published paper. We believe the completion of this evaluation process has brought clarity to the issue.”

Broad consensus EFSA’s final statement considered the independent assessments of the paper by organisations of six EU Member States: Belgium, Denmark, France, Germany, Italy and the Netherlands. Full copies of these evaluations can be found in the annex of EFSA’s statement. EFSA noted the emergence of a broad European consensus, with the reviewed Member State assessments finding the conclusions of Séralini et al. were not supported by the data presented in the study. Four of the national evaluations found the paper did not provide scientific information that would indicate the necessity to reopen the risk assessment of NK603 or glyphosate. The exceptions were France’s High Council of Biotechnology and Italy, whose assessments did not examine this issue. Member States also identified many of the same weaknesses in the methodology and design of the paper as raised by EFSA. Unclear study objectives, the low number of rats used in each treatment group, a lack of detail on the feed and treatment formulation, key information missing on the statistical methods employed and incomplete endpoint reporting were all highlighted by Member State organisations. Inadequate sample size In the course of the review process, EFSA had requested Séralini et al. to provide further information on their study documentation. No such material had reached the Authority before publication of this statement. However, on 9 November 2012, Séralini et al. published a general reply to the reactions from across the globe to their paper.

After carefully examining the publication, EFSA concluded it provided only a limited amount of relevant information which failed to address the majority of the outstanding questions raised in the Authority’s first statement. In their ‘Answer to critics’ document, Séralini et al. stated the sample size of their treatment groups was too small to allow them to draw conclusions with regard to long-term carcinogenicity and mortality. EFSA noted this acknowledgement from the authors is inconsistent with the overall conclusions they made in the paper regarding the tumours and mortality. EFSA’s evaluation of the Séralini et al. article was in keeping with its mission to review all relevant scientific literature for GMO risk assessment. The Authority remains committed to monitoring relevant literature on an ongoing basis to ensure the advice it provides is up to date.