首页
登录
职称英语
Researchers have reconstructed an ancient human genome(基因组)for the first tim
Researchers have reconstructed an ancient human genome(基因组)for the first tim
游客
2024-05-01
51
管理
问题
Researchers have reconstructed an ancient human genome(基因组)for the first time, thanks to the discovery of a 4000-year-old strand of hair in Greenland permafrost(永冻土). Experts say that similar techniques could be employed in many other ways, such as analyzing the DNA of South American mummies or crime victims.
The sample was taken from one of four strands of hair collected in Greenland by Danish archaeologists in the 1980s. The hairs are the only known human remains from the earliest people to settle in Greenland. A chance conversation alerted University of Copenhagen researcher Eske Willerslev, who was just back from two unsuccessful months in Greenland searching for human remains to test for DNA, to the sample, which had been stored at the National Museum of Denmark for more than 20 years.
Once they had the hairs in their possession, Willerslev and colleagues set about sequencing the sample. The team used dozens of sequencing machines to identify and map DNA fragments in the hair shafts, a process that took nearly 2 months. The data revealed more than 80% of the genome, coverage comparable to what can be done with a modern human genome.
"From the DNA, we can tell a lot about the individual," says Willerslev. "He had brown eyes, brown skin, a tendency to baldness, and dry earwax." The researchers have named him "Inuk," which means "man" or "human" in Greenlandic.
The genome also sheds light on where the man’s relatives came from. When the researchers compared his DNA with that collected from more than 40 Arctic and native North American populations, they concluded that the first people to settle in Greenland were related to groups now living in northeastern Siberia. The analysis also revealed that these first colonists were not the ancestors of the Inuit who live on the island now.
The researchers say that when it comes to ancient DNA, the Greenland sample may amount to low-hanging fruit. The hair had been preserved by cold for thousands of years, ideal conditions for recovering DNA. "Working with these young permafrost samples is worlds apart from working with older, non-permafrost samples," says Adrian Briggs, a researcher at the Max Planck Institute. He notes that the Greenland sample contains tens of thousands of times more DNA than typically found in Neandertal and early modern human samples from warmer environments.
Yet the discovery shows that with ever-cheaper genetic sequencing and faster computers, it is possible to recover a full nuclear DNA sequence from an ancient human, even when the genome is broken into tiny fragments. The nicest thing this paper shows is that the application of next-generation sequencing techniques is really going to expand what we can do with ancient DNA. [br] According to the researchers, the genetic sequencing techniques _____.
选项
A、need improving
B、are promising
C、must be computer-assisted
D、will not be limited to DNA studies
答案
B
解析
最后一段的内容强调了基因测序技术的用处,而第2句中的nicest,is really going to expand…等词都表明基因测序技术有很好的前景,因此,本题应选B。
转载请注明原文地址:https://tihaiku.com/zcyy/3579529.html
相关试题推荐
Plato,anancientGreekphilosopher,believedthatmenaredividedintothre
Researchershavereconstructedanancienthumangenome(基因组)forthefirsttim
Researchershavereconstructedanancienthumangenome(基因组)forthefirsttim
Researchershavereconstructedanancienthumangenome(基因组)forthefirsttim
AstudyledbyresearchersattheUniversityofPennsylvaniaindicatesthat
AstudyledbyresearchersattheUniversityofPennsylvaniaindicatesthat
AstudyledbyresearchersattheUniversityofPennsylvaniaindicatesthat
Researchershavefoundthatpeople’smentalabilitiespeakat22beforebegi
Researchershavefoundthatpeople’smentalabilitiespeakat22beforebegi
Researchershavefoundthatpeople’smentalabilitiespeakat22beforebegi
随机试题
[originaltext]TheworldwideorganizationoftheRedCrossstemsfromtheide
简述电视传播的弱点。
通常讲,闪烁频率低于2.5Hz或高于15Hz都是可以忽略的。当闪烁频率在4Hz-
如图10,点E是AD上一点,AB=AC,
陈老师在音符时值的教学中,没有采用数学运算方式,而是将音符时值的时间关系与音响结
某男,65岁,患慢性充血性心力衰竭和骨质疏松症,长期口服地高辛片剂和钙片,因眩晕
国家电网公司变电检测管理规定中省检修公司变电检修中心应履行的职责有那些()。
B左边四个图形可以拼合成如下图形:
ABC会计师事务所拟承接J集团的集团财务报表审计业务。集团项目合伙人在考虑承接业
保证安全生产投入是实现安全生产的重要基础。安全生产投入资金由谁保证应根据企业性质
最新回复
(
0
)