2. 考研
  3. 【F1】A tiny number of people in the world carry genetic mutations that were thought to guarantee the development of severe childh

【F1】A tiny number of people in the world carry genetic mutations that were thought to guarantee the development of severe childh

admin2019-08-08  61
问题    【F1】A tiny number of people in the world carry genetic mutations that were thought to guarantee the development of severe childhood diseases, but these people do not actually have these diseases, according to a new study.
   In the study, researchers looked at the genetic data from more than half a million people from around the world. The scientists found 13 adults who carried the exact genetic mutations that cause diseases such as cystic fibrosis, which severely affects the lungs and digestive system, or a condition called Pfeiffer syndrome, which affects the bones of the skull. But despite the mutations, these adults had not developed these diseases.
   【F2】The results may be the first step toward identifying ways to prevent other people who also have these mutations from developing such diseases.
   The idea of the new research was, "study the healthy, don’t just study the sick," said Stephen Friend, a co-author of the study and a researcher at Sage Bionetworks in Seattle. In the study, the researchers looked at the genetic data of about 589,000 people. The information came from 12 previously collected data sets. 【F3】The researchers said they wanted to see if, among these people, there were any individuals who remained healthy despite carrying certain genetic mutations linked to severe childhood disorders.
   The researchers focused on diseases that are caused by mutations in a single gene, and have severe symptoms that generally show up early in childhood. In their search, the investigators found three adults who did not have cystic fibrosis, despite having mutations on both copies of the CFTR gene, which normally causes the condition, according to the study.
   The researchers said they don’t know for sure exactly why these people failed to develop the diseases that they seemed genetically destined for. 【F4】However, one possibility is that these individuals also have other genes that somehow suppress these disease-causing mutations, preventing these people from getting sick, said study co-author Rong Chen.
   The researchers noted the study had limitations. For example, the investigators said they were not able to contact the 13 people identified in the study, because the researchers did not have the means to obtain consent from the people to do so. 【F5】This means the scientists were not able to interview the individuals, physically examine them or verify the accuracy of the genetic information that the researchers got from the previously collected data sets. It is therefore not possible to determine with certainty that these people are truly resistant to these diseases without further information, the researchers said.
【F1】
选项
答案世界上有一小部分人发生了基因突变，很可能因而患上严重的儿童疾病。但一项新研究表明，这些人实际上并没有患病。
解析 ①本句是but连接的并列复合句。分句1的主干是简单的主谓宾结构，其中包含了that引导的定语从句，修饰先行词genetic mutations“基因突变”，说明此类突变的危害(会导致携带者患上严重的儿童疾病)，that在该定语从句中既充当引导词，又充当主语。②分句2也是简单的主谓宾结构：句末的介宾短语according to a new study可视为插入语，补充说明整个并列句所述内容的出处。
转载请注明原文地址:https://www.kaotiyun.com/show/uG2Z777K
0

考研英语一

相关试题推荐
随机试题
最新回复(0)