IQ-gene

    In the angry debate over how much of IQ comes from the genes that children inherit from parents and how much comes from experiences, one little fact gets overlooked¹ ： no one has identified any genes ( other than² those that cause retardation) that affect intelligence. So researchers led by Robert Plomin of London"sInstituteofPsychiatrydecided to look for some. They figured that if you want to find a “ smart gene, ” you should look in smart kids. They therefore examined the DNA of students like those who are so bright that they take college entrance exams four years early — and still score at Princeton-caliber levels³. The scientists found what they sought.⁴ “ We have，” says Plomin，“ the first specific gene ever associated with general intelligence. ”

    Plomin"s colleagues drew blood from two groups of 51 children each, all 6 to 15 years old and living in six counties aroundCleveland. In one group, the average IQ is 103. All the children are white. Isolating the blood cells, the researchers then examined each child"s chromosome 6. Of the 37 landmarks on chromosome 6 that the researchers looked for, one jumped out⁵ ： a form of gene called IGF2R occurred in twice as many children in the high-IQ group as in the average group — 32 percent versus 16 percent. The study, in the May issue of the journal Psychological Science, concludes that it is this form of the IGF2R gene that contributes to intelligence.

    Some geneticists see major problems with the IQ-gene study⁶. One is the possibility that Plomin"s group fell for⁷ ” chopsticks fallacy". Geneticists might think they"ve found a gene for chopsticks flexibility, but all they"ve really found is a gene more common in Asians than, say, Africans. Similarly, Plomin"s IQ gene might simply be one that is more common in groups that emphasize academic achievement⁸. “ What is the gene that they"ve found reflects ethnicity?" asks geneticist Andrew Feinberg ofJohnsHopkinsUniversity. “ That alone might explain the link to intelligence, since IQ tests are known for being culturally sensitive and affected by a child"s environment. ” And Neil Risch of Standford University points out that if you look for 37 genes on a chromosome，as the researchers did，and find that one is more common in smarter kids，that might reflect pure chance rather than a causal link between the gene and intelligence⁹. Warns Feinberg： “I would take these findings with a whole box of salt¹⁰. ”

词汇：

psychiatry / saɪˈkaɪətri/ n. 精神病学 

caliber /"kælɪbə/ n. 能力，才干，水准
chopsticks /"tʃɒpstɪks/ n. 筷子 

ethnicity /eθˈnɪsəti/ n. 民族特性
figure /ˈfiɡə/ vt. 估计，想象 

geneticist /dʒəˈnetɪsɪst/ n. 遗传学家
fallacy /ˈfæləsi/ n. 谬误

causal / ˈkɔ:zl / adj.原因的，因果关系的

注释：

1.one little fact gets overlooked：有一个小事实被忽视了。这里get与过去分词一起相当于被动语态。
2.other than：除了……（以外）
3.score at Princeton-caliber levels：得分可列入像美国普林斯顿大学那样的重点大学的才子之列。
4.The scientists found what they sought.科学家们发现了他们所要寻找的东西。
5.jump out：显得突出
6.see major problems with the IQ-gene study：发现了智商基因研究的主要问题
4.fall for：受到……的蒙蔽
8.groups that emphasize academic achievement：强调学术成就的群体
9. ... that might reflect pure chance rather than a causal link between the gene and intelligence. ……那也许纯属偶然，而不反映基因与智力间的因果关系。
10. I would take these findings with a whole box of salt.我对实验的发现抱很大的怀疑。斜体部分 源自固定短语take sth. with a grain of salt，意为“抱有怀疑”。

A gene for chopsticks flexibility is found to be____

A:unrelated to the ability to use chopsticks B:related to the ability to use chopsticks C:unrelated to the ability to use forks D:related to the ability to use forks

At 18, Ashanthi DeSilva of suburban Cleveland is a living symbol of one of the great intellectual achievements of the 20th century. Born with an extremely rare and usually fatal disorder that left her without a functioning immune system (the "bubble-boy disease", named after an earlier victim who was kept alive for years in a sterile plastic tent), she was treated beginning in 1990 with a revolutionary new therapy that sought to correct the defect at its very source, in the genes of her white blood cells. It worked. Although her last .gene-therapy treatment was in 1992, she is completely healthy with normal immune function, according to one of the doctors who treated her, W. French Anderson of the University of Southern California. Researchers have long dreamed of treating diseases from hemophilia to cancer by replacing mutant genes with normal ones. And the dreaming may continue for decades more. "There will be a gene-based treatment for essentially every disease, " Anderson says, "within 50 years. "
It’s not entirely clear why medicine has been so slow to build on Anderson’s early success. The National Institutes of Health budget office estimates it will spend $432 million on gene-therapy research in 2005, and there is no shortage of promising leads. The therapeutic genes are usually delivered through viruses that don’t cause human disease. "The virus is sort of like a Trojan horse," says Ronald Crystal of New York Presbyterian/Weill Comell Medical College. "The cargo is the gene."
At the University of Pennsylvania’s Abramson Cancer Center, immunologist Carl June recently treated HIV patients with a gene intended to help their cells resist the infection. At Comell University, researchers are pursuing gene-based therapies for Parkinson’s disease and a rare hereditary disorder that destroys children’s brain cells. At Stanford University and the Children’s Hospital of Philadelphia, researchers are trying to figure out how to help patients with hemophilia who today must inject themselves with expensive clotting drugs for life. Animal experiments have shown great promise.
But somehow, things get lost in the translation from laboratory to patient. In human trials of the hemophilia treatment, patients show a response at first, but it fades over time. And the field has still not recovered from the setback it suffered in 1999, when Jesse Gelsinger, an 18-year-old with a rare metabolic disorder, died after receiving an experimental gene therapy at the University of Pennsylvania. Some experts worry that the field will be tarnished further if the next people to benefit are not patients but athletes seeking an edge. This summer, researchers at the Sulk Institute in San Diego said they had created a "marathon mouse" by implanting a gene that enhances running ability; already, officials at the World Anti-Doping Agency are preparing to test athletes for signs of "gene doping". But the principle is the same, whether you’re trying to help a healthy runner run faster or allow a muscular-dystrophy patient to walk. "Everybody recognizes that gene therapy is a very good idea," says Crystal. "And eventually it’s going to work".
The case of Ashanthi Desilva is mentioned in the text to ______.

A:show the promise of gene-therapy B:give an example of modem treatment for fatal diseases C:introduce the achievement of Anderson and his team D:explain how gene-based treatment works

At 18, Ashanthi DeSilva of suburban Cleveland is a living symbol of one of the great intellectual achievements of the 20th century. Born with an extremely rare and usually fatal disorder that left her without a functioning immune system (the "bubble-boy disease", named after an earlier victim who was kept alive for years in a sterile plastic tent), she was treated beginning in 1990 with a revolutionary new therapy that sought to correct the defect at its very source, in the genes of her white blood cells. It worked. Although her last .gene-therapy treatment was in 1992, she is completely healthy with normal immune function, according to one of the doctors who treated her, W. French Anderson of the University of Southern California. Researchers have long dreamed of treating diseases from hemophilia to cancer by replacing mutant genes with normal ones. And the dreaming may continue for decades more. "There will be a gene-based treatment for essentially every disease, " Anderson says, "within 50 years. "
It’s not entirely clear why medicine has been so slow to build on Anderson’s early success. The National Institutes of Health budget office estimates it will spend $432 million on gene-therapy research in 2005, and there is no shortage of promising leads. The therapeutic genes are usually delivered through viruses that don’t cause human disease. "The virus is sort of like a Trojan horse," says Ronald Crystal of New York Presbyterian/Weill Comell Medical College. "The cargo is the gene."
At the University of Pennsylvania’s Abramson Cancer Center, immunologist Carl June recently treated HIV patients with a gene intended to help their cells resist the infection. At Comell University, researchers are pursuing gene-based therapies for Parkinson’s disease and a rare hereditary disorder that destroys children’s brain cells. At Stanford University and the Children’s Hospital of Philadelphia, researchers are trying to figure out how to help patients with hemophilia who today must inject themselves with expensive clotting drugs for life. Animal experiments have shown great promise.
But somehow, things get lost in the translation from laboratory to patient. In human trials of the hemophilia treatment, patients show a response at first, but it fades over time. And the field has still not recovered from the setback it suffered in 1999, when Jesse Gelsinger, an 18-year-old with a rare metabolic disorder, died after receiving an experimental gene therapy at the University of Pennsylvania. Some experts worry that the field will be tarnished further if the next people to benefit are not patients but athletes seeking an edge. This summer, researchers at the Sulk Institute in San Diego said they had created a "marathon mouse" by implanting a gene that enhances running ability; already, officials at the World Anti-Doping Agency are preparing to test athletes for signs of "gene doping". But the principle is the same, whether you’re trying to help a healthy runner run faster or allow a muscular-dystrophy patient to walk. "Everybody recognizes that gene therapy is a very good idea," says Crystal. "And eventually it’s going to work".
Anderson’s early success has ______.

A:greatly speeded the development of medicine B:brought no immediate progress in the research of gene-therapy C:promised a cure to every disease D:made him a national hero

At 18, Ashanthi DeSilva of suburban Cleveland is a living symbol of one of the great intellectual achievements of the 20th century. Born with an extremely rare and usually fatal disorder that left her without a functioning immune system (the "bubble-boy disease", named after an earlier victim who was kept alive for years in a sterile plastic tent), she was treated beginning in 1990 with a revolutionary new therapy that sought to correct the defect at its very source, in the genes of her white blood cells. It worked. Although her last .gene-therapy treatment was in 1992, she is completely healthy with normal immune function, according to one of the doctors who treated her, W. French Anderson of the University of Southern California. Researchers have long dreamed of treating diseases from hemophilia to cancer by replacing mutant genes with normal ones. And the dreaming may continue for decades more. "There will be a gene-based treatment for essentially every disease, " Anderson says, "within 50 years. "
It’s not entirely clear why medicine has been so slow to build on Anderson’s early success. The National Institutes of Health budget office estimates it will spend $432 million on gene-therapy research in 2005, and there is no shortage of promising leads. The therapeutic genes are usually delivered through viruses that don’t cause human disease. "The virus is sort of like a Trojan horse," says Ronald Crystal of New York Presbyterian/Weill Comell Medical College. "The cargo is the gene."
At the University of Pennsylvania’s Abramson Cancer Center, immunologist Carl June recently treated HIV patients with a gene intended to help their cells resist the infection. At Comell University, researchers are pursuing gene-based therapies for Parkinson’s disease and a rare hereditary disorder that destroys children’s brain cells. At Stanford University and the Children’s Hospital of Philadelphia, researchers are trying to figure out how to help patients with hemophilia who today must inject themselves with expensive clotting drugs for life. Animal experiments have shown great promise.
But somehow, things get lost in the translation from laboratory to patient. In human trials of the hemophilia treatment, patients show a response at first, but it fades over time. And the field has still not recovered from the setback it suffered in 1999, when Jesse Gelsinger, an 18-year-old with a rare metabolic disorder, died after receiving an experimental gene therapy at the University of Pennsylvania. Some experts worry that the field will be tarnished further if the next people to benefit are not patients but athletes seeking an edge. This summer, researchers at the Sulk Institute in San Diego said they had created a "marathon mouse" by implanting a gene that enhances running ability; already, officials at the World Anti-Doping Agency are preparing to test athletes for signs of "gene doping". But the principle is the same, whether you’re trying to help a healthy runner run faster or allow a muscular-dystrophy patient to walk. "Everybody recognizes that gene therapy is a very good idea," says Crystal. "And eventually it’s going to work".
Which of the following is true according to the text

A:Ashanthi needs to receive gene-therapy treatment constantly. B:Despite the huge funding, gene researches have shown few promises. C:Therapeutic genes are carried by harmless viruses. D:Gene-doping is encouraged by world agencies to help athletes get better scores.

Among all the fast growing science and technology, the research of human genes, or biologi cal engineering as people call it, is drawing more and more attention now. Sometimes it’s a hot topic discussed by people.
The greatest thing that gene technology can do is to cure serious diseases that doctors at present can almost do nothing with, such as cancer and heart disease. Every year, millions of people are murdered by these two killers. And to date, doctors have not found an effective way to cure them. But if the gene technology is applied, not only these two diseases can be cured completely, bringing happiness and more living days to the patients, but also the great amount of money people spend on curing their diseases can be saved, therefore it benefits the economy as well. In addition, human life span(寿命)can be prolonged.
Gene technology can help people to give birth to more healthy and clever children. Some families, with the English imperial(皇帝的)family being a good example, have hereditary(遗传的)diseases. This means their children will for sure have the family disease, which is a great trouble for these families. In the past, doctors could do nothing about hereditary diseases. But gene technology can solve this problem perfectly. Scientists just need to find the wrong gene and correct it, and a healthy child will be born.
Some people are worrying that the gene research can be used to manufacture(生产)human beings in large quantities. In the past few years, scientists have succeeded in cloning a sheep; therefore these people predict that human babies would soon be cloned. But I believe cloned babies will not come out in large quantities, for most couples in the world can have babies in very normal way. Of course, the governments must take care to control gene technology.

A:Expressing the writer’s idea that gene technology will benefit people. B:Telling people the advantages and disadvantages of gene technology. C:Telling the readers that gene technology will not benefit people. D:Explaining that gene technology will also do harm to the humanity.

Defective Genes and Human Health Each of us carries about half a dozen defective(有缺点的) genes. We remain blissfully(快乐地) unaware of this fact unless we, or one of our close relatives, are amongst the many millions who suffer from a genetic disease. About one in ten people has, or will develop at some later stage, an inherited(遗传的)genetic disorder, and approximately 2,800 specific conditions are known to be caused by defects (mutations) in just one of the patient’’s genes. Some single gene disorders are quite common-—cystic(胞状的) fibrosis (纤维化) is found in one out of every 2,500 babies born in the Western World—and in total, diseases that can be traced to single gene defects account for about 5% of all admissions to children’’s hospitals. Most of us do not suffer any harmful effects from our defective genes because we carry two copies of nearly all genes, one derived from our mother and the other from our father. The only exceptions to this rule are the genes found on the male sex chromosomes (染色体) Males have one X and one Y chromosome, the former from the mother and the latter from the father, so each cell has only one copy of the genes on these chromosomes. In the majority of cases, one normal gene is sufficient to avoid all the symptoms of disease. If the potentially harmful gene is recessive(后退的), then its normal counterpart(配对的) will carry out all the tasks assigned to both. Only if we inherit from our parents two copies of the same recessive gene will a disease develop. On the other hand, if the gene is dominant(显性的), it alone can produce the disease, even if its counterpart is normal. Clearly only the children of a parent with the disease can be affected, and then average only half the children will be affected. Huntington’’s chorea (舞蹈病) , a severe disease of the nervous system, which becomes apparent only in adulthood, is an example of a dominant genetic disease. Finally, there are the X chromosome-linked genetic diseases. As males have only one copy of the genes from this chromosome, there are no others available to fulfill the defective gene’’s function. Examples of such diseases are Duchenne muscular dystrophy(营养不良) and, perhaps most well known of all, hemophilia(血友病). Queen Victoria was a carrier of the defective gene responsible for hemophilia, and through her it was transmitted to the royal families of Russia, Spain, and Prussia. Minor cuts and bruises, which would do little harm to most people, can prove fatal to hemophiliacs, who lack the proteins(Factors VIII and IV) (凝血因子VIII和IV)involved in the clotting(血凝结)of blood, which are coded for by the defective genes. Sadly, before these proteins were made available through genetic engineering, hemophiliacs were treated with proteins isolated from human blood. Some of this blood was contaminated(污损) with the AIDS virus, and has resulted in tragic(悲惨的) consequences for many hemophiliacs. Use of genetically engineered proteins in the rapeutic applications, rather than blood products, will avoid these problems in the future. Not all defective genes necessarily produce detrimental(有害的)effects, since the environment in which the gene operates is also of importance. A classic example of a genetic disease having a beneficial effect on survival is illustrated by the relationship between sickle-cell,(镶形血球)anemia (贫血症) and malaria(疟病). Only individuals having two copies of the sickle-cell gene and one normal gene are unaffected and, more importantly, are able to resist infection(传染) by malarial parasites (寄生虫). The clear advantage, in this case, of having one defective gene explains why this gene is common in populations in those areas of the world where malaria is endemic(特有的). We can infer from para. 4 that______.

A:half of the children will be affected by the dominant genetic diseases B:about 50% children of the parents with the dominant genetic diseases can be affected C:when a child becomes an adult, a dominant genetic disease will become apparent D:a normal gene will carry out all the tasks assigned to it and its counterpart, when the latter is dominant

Defective Genes and Human Health Each of us carries about half a dozen defective(有缺点的) genes. We remain blissfully(快乐地) unaware of this fact unless we, or one of our close relatives, are amongst the many millions who suffer from a genetic disease. About one in ten people has, or will develop at some later stage, an inherited(遗传的)genetic disorder, and approximately 2,800 specific conditions are known to be caused by defects (mutations) in just one of the patient’’s genes. Some single gene disorders are quite common-—cystic(胞状的) fibrosis (纤维化) is found in one out of every 2,500 babies born in the Western World—and in total, diseases that can be traced to single gene defects account for about 5% of all admissions to children’’s hospitals. Most of us do not suffer any harmful effects from our defective genes because we carry two copies of nearly all genes, one derived from our mother and the other from our father. The only exceptions to this rule are the genes found on the male sex chromosomes (染色体) Males have one X and one Y chromosome, the former from the mother and the latter from the father, so each cell has only one copy of the genes on these chromosomes. In the majority of cases, one normal gene is sufficient to avoid all the symptoms of disease. If the potentially harmful gene is recessive(后退的), then its normal counterpart(配对的) will carry out all the tasks assigned to both. Only if we inherit from our parents two copies of the same recessive gene will a disease develop. On the other hand, if the gene is dominant(显性的), it alone can produce the disease, even if its counterpart is normal. Clearly only the children of a parent with the disease can be affected, and then average only half the children will be affected. Huntington’’s chorea (舞蹈病) , a severe disease of the nervous system, which becomes apparent only in adulthood, is an example of a dominant genetic disease. Finally, there are the X chromosome-linked genetic diseases. As males have only one copy of the genes from this chromosome, there are no others available to fulfill the defective gene’’s function. Examples of such diseases are Duchenne muscular dystrophy(营养不良) and, perhaps most well known of all, hemophilia(血友病). Queen Victoria was a carrier of the defective gene responsible for hemophilia, and through her it was transmitted to the royal families of Russia, Spain, and Prussia. Minor cuts and bruises, which would do little harm to most people, can prove fatal to hemophiliacs, who lack the proteins(Factors VIII and IV) (凝血因子VIII和IV)involved in the clotting(血凝结)of blood, which are coded for by the defective genes. Sadly, before these proteins were made available through genetic engineering, hemophiliacs were treated with proteins isolated from human blood. Some of this blood was contaminated(污损) with the AIDS virus, and has resulted in tragic(悲惨的) consequences for many hemophiliacs. Use of genetically engineered proteins in the rapeutic applications, rather than blood products, will avoid these problems in the future. Not all defective genes necessarily produce detrimental(有害的)effects, since the environment in which the gene operates is also of importance. A classic example of a genetic disease having a beneficial effect on survival is illustrated by the relationship between sickle-cell,(镶形血球)anemia (贫血症) and malaria(疟病). Only individuals having two copies of the sickle-cell gene and one normal gene are unaffected and, more importantly, are able to resist infection(传染) by malarial parasites (寄生虫). The clear advantage, in this case, of having one defective gene explains why this gene is common in populations in those areas of the world where malaria is endemic(特有的). We can infer from para. 4 that______.

A:half of the children will be affected by the dominant genetic diseases B:about 50% children of the parents with the dominant genetic diseases can be affected C:when a child becomes an adult, a dominant genetic disease will become apparent D:a normal gene will carry out all the tasks assigned to it and its counterpart, when the latter is dominant

Defective Genes and Human Health Each of us carries about half a dozen defective(有缺点的) genes. We remain blissfully(快乐地) unaware of this fact unless we, or one of our close relatives, are amongst the many millions who suffer from a genetic disease. About one in ten people has, or will develop at some later stage, an inherited(遗传的)genetic disorder, and approximately 2,800 specific conditions are known to be caused by defects (mutations) in just one of the patient’’s genes. Some single gene disorders are quite common-—cystic(胞状的) fibrosis (纤维化) is found in one out of every 2,500 babies born in the Western World—and in total, diseases that can be traced to single gene defects account for about 5% of all admissions to children’’s hospitals. Most of us do not suffer any harmful effects from our defective genes because we carry two copies of nearly all genes, one derived from our mother and the other from our father. The only exceptions to this rule are the genes found on the male sex chromosomes (染色体) Males have one X and one Y chromosome, the former from the mother and the latter from the father, so each cell has only one copy of the genes on these chromosomes. In the majority of cases, one normal gene is sufficient to avoid all the symptoms of disease. If the potentially harmful gene is recessive(后退的), then its normal counterpart(配对的) will carry out all the tasks assigned to both. Only if we inherit from our parents two copies of the same recessive gene will a disease develop. On the other hand, if the gene is dominant(显性的), it alone can produce the disease, even if its counterpart is normal. Clearly only the children of a parent with the disease can be affected, and then average only half the children will be affected. Huntington’’s chorea (舞蹈病) , a severe disease of the nervous system, which becomes apparent only in adulthood, is an example of a dominant genetic disease. Finally, there are the X chromosome-linked genetic diseases. As males have only one copy of the genes from this chromosome, there are no others available to fulfill the defective gene’’s function. Examples of such diseases are Duchenne muscular dystrophy(营养不良) and, perhaps most well known of all, hemophilia(血友病). Queen Victoria was a carrier of the defective gene responsible for hemophilia, and through her it was transmitted to the royal families of Russia, Spain, and Prussia. Minor cuts and bruises, which would do little harm to most people, can prove fatal to hemophiliacs, who lack the proteins(Factors VIII and IV) (凝血因子VIII和IV)involved in the clotting(血凝结)of blood, which are coded for by the defective genes. Sadly, before these proteins were made available through genetic engineering, hemophiliacs were treated with proteins isolated from human blood. Some of this blood was contaminated(污损) with the AIDS virus, and has resulted in tragic(悲惨的) consequences for many hemophiliacs. Use of genetically engineered proteins in the rapeutic applications, rather than blood products, will avoid these problems in the future. Not all defective genes necessarily produce detrimental(有害的)effects, since the environment in which the gene operates is also of importance. A classic example of a genetic disease having a beneficial effect on survival is illustrated by the relationship between sickle-cell,(镶形血球)anemia (贫血症) and malaria(疟病). Only individuals having two copies of the sickle-cell gene and one normal gene are unaffected and, more importantly, are able to resist infection(传染) by malarial parasites (寄生虫). The clear advantage, in this case, of having one defective gene explains why this gene is common in populations in those areas of the world where malaria is endemic(特有的). We can infer from para. 4 that______.

A:half of the children will be affected by the dominant genetic diseases B:about 50% children of the parents with the dominant genetic diseases can be affected C:when a child becomes an adult, a dominant genetic disease will become apparent D:a normal gene will carry out all the tasks assigned to it and its counterpart, when the latter is dominant