Scientists unlock gene secrets of opium poppy drug

Updated 08 July 2012
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Scientists unlock gene secrets of opium poppy drug

LONDON: Scientists have unraveled exactly how opium poppies produce a non-addictive compound that can both suppress coughs and kill tumor cells, paving the way for improved production of the medicine.
Opium poppies, the source of illicit heroin, are also important for producing medical painkillers such as morphine and codeine, along with noscapine, which has been used for decades as a cough suppressant.
More recently, researchers have found noscapine is also a potent anti-cancer agent, prompting clinical tests into its role in fighting blood cancer.
The discovery that a cluster of 10 genes is responsible for the synthesis of noscapine inside the poppies means plant breeders can now develop high-yielding varieties. It may also help scientists in future produce the drug in factories.
The findings by researchers at the University of York and GlaxoSmithKline were published on Thursday in the journal Science.
British-based GSK is a leading producer of opium-based ingredients, supplying around 20 percent of the world’s medicinal opiate needs from poppies grown by farmers in Tasmania.
The fact that all the genes associated with noscapine are clustered together makes life much easier for plant breeders who can use the information to develop high-yielding commercial noscapine poppies.
In contrast to illegal opium production in countries like Afghanistan, where harvesting is done by hand by lancing poppy heads, commercial pharmaceutical production is highly mechanized, with farmers using modern combine harvesters.
That makes commercial poppy cultivation a cost-effective process, even though most medicines today are produced by chemical synthesis or biotechnology.
“The poppy plant is very efficient at producing these compounds,” said Ian Graham, director of the Center for Novel Agricultural Products at York.
Working back from a strain of poppies producing high levels of noscapine, Graham and colleagues followed the trail of genes linked to the chemical to home in on the cluster of 10 specific genes central to production of the compound.
The cluster of genes, all of which are inherited together, is the most complex ever found in plants.
Noscapine was first discovered in the early 19th century and has been used to suppress coughs since the 1950s, but interest in the compound has grown since 1998 when scientists demonstrated that it acts as a potent anti-tumor agent.
It functions in a similar way to Taxol, a cancer drug originally isolated from the bark of the Pacific yew tree and commercialized by Bristol-Myers Squibb.
Cougar Biotechnology, now part of Johnson & Johnson, has been studying noscapine as a treatment for multiple myeloma, a type of cancer affecting the plasma cells in bone marrow.

 


‘Results’ needed from Myanmar over Rohingya return: UNHCR head

Updated 50 min 58 sec ago
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‘Results’ needed from Myanmar over Rohingya return: UNHCR head

  • A UN fact-finding mission called for Myanmar’s top generals to be prosecuted for “genocide”
  • Myanmar pejoratively labels the Rohingya as “Bengali,” implying they are illegal interlopers

YANGON: Myanmar must “show results” to convince Rohingya refugees to return, the UN’s High Commissioner for Refugees Filippo Grandi said Friday at the end of his first visit to Myanmar since the crackdown against Rohingya Muslims in 2017.
A brutal military campaign in western Rakhine state forced some 740,000 Rohingya over the border into Bangladesh.
Around one million Rohingya now languish in sprawling refugee camps from various waves of persecution.
A UN fact-finding mission called for Myanmar’s top generals to be prosecuted for “genocide” and the International Criminal Court (ICC) has started preliminary investigations.
During his visit Grandi spoke with both Rohingya and ethnic Rakhine Buddhist communities in Maungdaw and Buthidaung in northern Rakhine, the epicenter of the violence.
He also held discussions with officials in capital Naypyidaw, including civilian leader Aung San Suu Kyi, describing all talks as “constructive.”
“My message is: ‘please accelerate’, because it has been very slow in the implementation in this first year. We need to show results,” he told AFP in an interview in Yangon.
“This is not enough to convince people to come back,” he said.
Grandi visited the camps in Bangladesh in April.
The two countries have signed a repatriation agreement but so far virtually no refugees have returned, fearing for their safety and unconvinced they will be granted citizenship.
Myanmar pejoratively labels the Rohingya as “Bengali,” implying they are illegal interlopers and the community has had its rights eroded over decades.
Gaining independent access to northern Rakhine is difficult with most journalists, observers and diplomats only allowed on brief chaperoned visits.
Grandi defended the UNHCR’s involvement in a plan by the Bangladeshi government to move some 100,000 refugees onto low-lying island Bhashan Char.
The area in the Bay of Bengal is prone to flooding and cyclones.
Rights groups oppose the scheme that has also so far been universally rejected by the Rohingya themselves.
The refugee agency must be “involved” to have the necessary information in order to take a stance on the issue, Grandi said.
“We’re still at that stage, no more than that.”
He also visited camps near Rakhine’s capital Sittwe, where nearly 130,000 Rohingya have been confined since a previous bout of violence in 2012.
Myanmar has announced it will close the camps but many are skeptical the displaced will enjoy more freedoms.
Grandi said the UNHCR would reconsider its role in providing services if conditions did not substantially improve.
“To simply transform the camps, upgrade the camps, upgrade the houses, for example, but leave them in the same situation will not be a solution,” he said.