What is the Difference Between Random and Imprinted X Inactivation?
🆚 Go to Comparative Table 🆚Random X inactivation and imprinted X inactivation are two distinct mechanisms that result in the inactivation of X chromosomes in female mammals. The main differences between these two processes are:
- Timing: Random X inactivation occurs around the time of implantation, while imprinted X inactivation occurs earlier in development.
- Chromosome: Imprinted X inactivation specifically inactivates the paternal X chromosome, while random X inactivation inactivates one of the two X chromosomes (either maternal or paternal) randomly.
- Stability: Imprinted X inactivation is less stable and less complete than random X inactivation.
- Mechanism: Both processes involve the expression of X-linked non-protein coding Xist RNA, but they are regulated by different mechanisms. Imprinted X inactivation is regulated by genomic imprinting, while random X inactivation is regulated by a different process.
- Tissue: Imprinted X inactivation occurs in extraembryonic lineages, such as placental tissue, while random X inactivation occurs in embryonic lineages.
In summary, random and imprinted X inactivation are distinct processes that result in the inactivation of X chromosomes in female mammals. They differ in timing, stability, mechanism, and the specific chromosome that is inactivated.
Comparative Table: Random vs Imprinted X Inactivation
Random and imprinted X inactivation are two forms of X inactivation occurring in female mammals. Both processes lead to transcriptional silencing of one X chromosome. Here is a table summarizing the differences between random and imprinted X inactivation:
Feature | Random X Inactivation | Imprinted X Inactivation |
---|---|---|
Definition | A normal X inactivation process in which both maternal and paternal X chromosomes have an equal probability to be inactivated. | A nonrandom X inactivation of the paternally derived X chromosome, primarily occurring in extraembryonic lineages of some eutherian species. |
Mechanism | Occurs in the cells of the embryo proper, involving the choice of the future inactive X chromosome. | Occurs in the extraembryonic lineages, with the paternal X chromosome being inactivated. |
Genomic Imprinting | Not related to genomic imprinting. | Associated with genomic imprinting, which is established in the germline. |
DNA Methylation | DNA methylation plays a role in random X inactivation. | DNA methylation contributes less to its stability and completion. |
In random X inactivation, both maternal and paternal X chromosomes have an equal probability of being inactivated, while in imprinted X inactivation, primarily the paternally derived X chromosome is chosen to be inactivated. Imprinted X inactivation is less complete and/or stable than the random form, and DNA methylation plays a lesser role in its stability and completion.
- X Inactivation vs Genomic Imprinting
- Uniparental Disomy vs Genomic Imprinting
- X vs Y Chromosomes
- XX vs XY Chromosomes
- In Situ Hybridization vs Immunohistochemistry
- Interchromosomal vs Intrachromosomal Recombination
- X Linked Dominant vs X Linked Recessive
- Recombination vs Crossing Over
- Cytoplasmic Inheritance vs Genetic Maternal Effect
- Transgenic vs Knockout Mice
- X linked vs Y linked Inheritance
- Immortalized vs Transformed Cells
- Random Orientation vs Independent Assortment
- Random Mutagenesis vs Site Directed Mutagenesis
- Mutation vs Recombination
- Parental Type vs Recombinant Type Chromosomes
- Crossover Frequency vs Recombination Frequency
- Somatic Hypermutation vs V(D)J Recombination
- Homologous Recombination vs Non-homologous Recombination