Next Generation Sequencing involves many short sequencing reads being assembled into large contiguous sequences using computer algorithms. Which of the following types of genomic regions make this process most difficult?

Question

BlackTom AI · Accepted Answer

In Next Generation Sequencing, the challenge is not only about sequencing length but about how reads map back to the genome and how contigs are assembled from those mappings.
Option a: Non-coding genes. While non-coding regions can be regulatory and sometimes repetitive, the primary difficulty in assembly often lies elsewhere. Non-coding genes themselves are not inherently problematic if their sequences are unique enough, so this option overstates the difficulty posed by non-coding regions alone.
Option b: Repetitive DNA sequences. This is the core issue in genome assembly: repetitive elements like transposons, satellite repeats, and segmental duplications create many nearly identical copies. Short reads can map to multiple genomic locations, causing ambiguity in placement, breaks in contigs, and incorrect assemblies. This leads to fragmented assemblies and gaps where repeats exceed read length or are highly similar.
Option c: Coding genes. Coding regions tend to be more conserved and often lie in unique sequences, making them comparatively easier to assemble and annotate. Although some gene families have paralogs, overall coding regions are not the primary source of assembly ambiguity.
Option d: Untranslated regions (UTRs) of coding genes. UTRs can be variable and sometimes repetitive, but they are generally shorter and not as repetitive as broad classes of repetitive DNA. While they can contribute to assembly challenges, they do not represent the dominant difficulty compared with long, highly repetitive elements.
Thus, the main factor that makes assembling short reads into long contigs particularly hard is the presence of repetitive DNA sequences, which create multiple equally plausible mapping locations and disrupt unambiguous assembly.

Next Generation Sequencing involves many short sequencing reads being assembled into large contiguous sequences using computer algorithms. Which of the following types of genomic regions make this process most difficult?单项选择题

类似问题

When exploring the human reference genome, you observe sequences with the prefix “chrUn” that are not part of the standard chromosomes (1-22, X, Y, or M). What do these sequences represent?

In the field of genomics, what is Genome Assembly?

What information is most likely to be lost during a genome assembly?

In the field of genomics, what is “Genome Assembly”?

Which of the following represents the correct sequence of steps in assembling and annotating a plant genome?

Which of the following statements correctly describes the impact of repetitive regions on genome assembly?

In genome construction, what are contigs assembled into?

Next Generation Sequencing involves many short sequencing reads being assembled into large contiguous sequences using computer algorithms. Which of the following types of genomic regions make this process most difficult?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单