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This is the VOA SpecialEnglish SCIENCE REPORT.
Scientists are questioning a widely reported finding from thefirst detailed study of the human gene map. The scientists disputethe finding that humans have only about thirty-thousand genes.
The new report suggests the true number could be much greater.The Genomics Institute of the Novartis Research Foundation in SanDiego, California prepared the report. It was published in Cellmagazine.
Other scientists have long argued about the number of humangenes. Some believe that humans have more than one-hundred-thousandgenes.
The issue seemed to be settled last February. That is when twocompeting teams of scientists published their efforts to map theposition of every human gene. A private American company calledCelera Genomics published one of the genetic maps. An internationalgroup called the Human Genome Project prepared the other. Each groupof scientists estimated that humans have about thirty-thousandgenes. That is about two times as many genes as some insects.
That number came as a surprise to some people. They wondered howan organism as complex as a human could have so few genes. It isimportant for scientists to identify every human gene in order tounderstand how cells work and what causes disease. Some scientistsbelieved the small number of genes was good news. It meant it wouldbe easier to identify all the genes and understand how they work.
In the new study, the Novartis scientists compared the two groupsof human genes from the two genetic maps. They found that the twogroups of scientists had identified two different sets of genes.Only about half the genes are common to both groups. The Novartisscientists say this means the number of human genes may be aboutforty-thousand.
The director of the Human Genome Project, Francis Collins, saidhe would not be surprised if humans were found to have more thanthirty-thousand genes. Celera's President, Craig Venter, notes thatthe process of discovering the real number is not simple. He saidmany of the genes noted in his company's study had not beenconfirmed.
The real number of human genes may not be known any time soon.Scientists say it probably will take years before we have a list ofthe genes that control human biology.
This VOA Special English SCIENCE REPORT was written by GeorgeGrow.