Genomic imprinting is an example of epigenetic inheritance.

Question

BlackTom AI · Accepted Answer

1) Relevant knowledge points and concepts
Genomic imprinting is a form of parent-of-origin–specific gene expression in which one allele (either maternal or paternal) is epigenetically marked so that it is expressed while the other allele is silenced. Epigenetic inheritance refers to heritable changes in gene expression that do not involve changes to the underlying DNA sequence, typically mediated by DNA methylation, histone modifications, and noncoding RNAs.

2) Step-by-step reasoning
Step 1: Define epigenetic inheritance — changes in gene activity transmitted through cell divisions (and sometimes across generations) that do not alter nucleotide sequence. Step 2: Describe imprinting mechanism — during gametogenesis, specific loci acquire differential DNA methylation and chromatin states depending on whether they are in sperm or egg. Step 3: Maintenance — after fertilization these epigenetic marks are maintained through mitotic cell divisions, causing one parental allele to remain silenced in the offspring’s somatic cells while the other allele is active. Step 4: Outcome — allele-specific expression is the direct result of those epigenetic marks, not a change in DNA sequence.

3) Intermediate/technical details
The primary molecular marks are differential DNA methylation at imprinting control regions and associated histone modifications; long noncoding RNAs (e.g., Xist-like mechanisms at some loci) also participate. Marks are erased and re-established in the germline, consistent with epigenetic (not permanent sequence) information.

4) Why the correct answer is correct
Because imprinting relies on reversible, heritable chemical modifications of DNA/chromatin that change expression without altering the sequence, it fits the definition of epigenetic inheritance. Classic examples include Igf2/H19 imprinting and imprinting disorders such as Prader–Willi and Angelman syndromes, which result from loss of parent-specific epigenetic control.

5) Why the other option is incorrect
B) False is incorrect because it denies the epigenetic nature of imprinting; in fact imprinting is one of the canonical examples used to illustrate epigenetic inheritance.

6) Conclusion
Therefore the correct choice is A) True, which matches the provided answer.

Genomic imprinting is an example of epigenetic inheritance.单项选择题

类似问题

The expression of a single allele is associated with which of the following?

The Igf2 gene is expressed from the paternal parent but not from the maternal parent. An ICR is located between the H19 and Igf2 genes. If a mutation eliminated this ICR, how would it affect the expression of the Igf2 gene?

Imprinted genes:

Imprinted genes:

Which of the following trees corresponds to a potential parse of the ambiguous sentence below, with correct syntactic categories? Some diagnostics are provided.

Which of the following sentences contain two non-finite verbs? Select all that apply.

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