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BEIJING, August 1 (Xinhuanet) -- U.S. researchers have discovered a genetic mutation unique to African Americans that links to heighten their asthma risk, according to reports published on Sunday in the journal Nature Genetics.Researchers of University of Chicago found a gene, PYHIN1, and its variations may account for asthma risk in people of African descent. In their study, they examined data from nine previous genome-wide association studies, totaling more than 2 million single nucleotide polymorphisms in 3,246 asthma patients and 3,385 control patient, 1,702 patient-parent groupings, 355 family-based cases, and 468 family-based controls.In the study, the researchers found that between 26 percent and 29 percent of people of African-descent carried at least one copy of the gene.  In particular, one polymorphism of the gene was 34 percent more likely found in African-American and Afro-Caribbean people with asthma.  More interestingly, this variant of the gene is rarely found in Caucasian people and in Latino population, it was found in less than 5 percent.This new variant is part of a family of genes linked with the body's response to viral infections. It is thought to be involved in interferon signaling, which could influence the occurrence of asthma.The team stressed that each gene variant on its own plays only a small role in increasing asthma risk, but that risk could be multiplied when combined with other risk genes and with environmental factors.

BEIJING, Aug. 1 (Xinhua) -- The provinces of Guizhou and Hunan reported their lowest levels of precipitation since 1951 in July, the China Meteorological Administration (CMA) said on Monday.Precipitation levels across the country saw a decrease of 8.7 percent from the average level of 115.9 mm in July, the lowest levels seen in 11 years, said Chen Zhenlin, an expert with the CMA.The average temperature recorded across the country in July was 22.1 degrees Celsius, up 0.7 degrees Celsius from the average level.

LOS ANGELES, June 24 (Xinhua) -- Near-Earth asteroid 2011 MD will whip past Earth on June 27, but will not pose any threat, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The asteroid will pass only 12,000 kilometers (7,500 miles) above the Earth's surface at about 9:30 EDT, according to JPL in Pasadena, Los Angeles.This small asteroid, only 5-20 meters in diameter, is in a very Earth-like orbit about the Sun, but an orbital analysis indicates there is no chance it will actually strike Earth on Monday, JPL said.If a rocky asteroid the size of 2011 MD were to enter Earth's atmosphere, it would be expected to burn up high in the atmosphere and cause no damage to Earth's surface, said JPL.The accompanying diagram gives a view of the asteroid's trajectory from the general direction of the Sun. This view indicates that 2011 MD will reach its closest Earth approach point in extreme southern latitudes (in fact over the southern Atlantic Ocean), according to JPL. The incoming trajectory leg passes several thousand kilometers outside the geosynchronous ring of satellites and the outgoing leg passes well inside the ring, JPL said.For a brief time, it may be bright enough to be seen even with a modest-sized telescope.One would expect an object of this size to come this close to Earth about every six years on average.The asteroid was discovered by the LINEAR near-Earth object discovery team observing from Socorro, New Mexico.

BEIJING, Sep. 13 (Xinhuanet) --Experts have called for a national drug-control system after a nationwide deficit of a life-saving drug, which has lasted at least three months.Doctors at a Beijing hospital said some specialized hospitals, which perform hundreds of cardiac operations every month, have been paralyzed by their lack of protamine sulfate, which is commonly administered after heart surgery to reverse the anticoagulant effects of heparin.The earliest report of a shortage was in Hubei province on July 21. This was followed by reports of shortages in Guangdong, Shandong and Liaoning provinces.The Shandong newspaper, Qilu Evening News, quoted a regional sales manager, surnamed Zhuang, as saying the province had been allocated 150 doses of protamine sulfate after Shanghai No 1 Biochemical and Pharmaceutical Co Ltd recently resumed production of the drug."But its monthly use here is usually 10,000 doses," he said.The Ministry of Health has denied it is responsible for supplies of the drug and passed the buck to the State Food and Drug Administration, claiming the latter is responsible for the supervision of medicines.Shen Chen, head of the publicity office of the State Food and Drug Administration, said he was unaware of the shortage, but said the administration is responsible for the quality of medicines, not the supply."Development and reform authorities oversee the medicines' prices, while the industrial and commercial authorities oversee the storage. The food and drug departments only cover the approval and quality of medicines."Industry insiders said one of the reasons for the shortage was the low profit margin, which discourages companies from mass producing the drug."Some companies can't earn enough to recover their costs, therefore it is almost impossible to maintain their enthusiasm for continuing production," said Lu Guoping, secretary-general of the Shanghai Pharmaceutical Trade Association.Lu said the government should issue policies to prevent future shortages of such medicines to avoid possible nationwide public health incidents.Yi Shenghua, a lawyer at Beijing Yingke Law Firm, said the country should have a unified system to guarantee the normal supply of medicines that are widely used and drug manufacturers should fulfill their responsibilities to society, even though there is no law stipulating they should produce specific medicines.He came up with two ways to deal with the problem of companies only producing profitable drugs."The government can order businesses to manufacture a certain amount of cheap medicines. Or it can offer financial assistance to subsidize cheap, but life-saving medicines."