Gene Duplication
Gene Duplication - Related Videos
02:37
Gene Duplication and Divergence
0 Views •
2021
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution. The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
02:05
Chromosome Duplication
0 Views •
2023
The process of chromosome duplication during cell division requires genome-wide disruption and re-assembly of chromatin. The chromatin structure must be accurately inherited, reassembled, and maintained in the daughter cells to ensure lineage propagation. The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
02:25
Centrosome Duplication
0 Views •
2023
The primary microtubule organizing center (MTOC) in animal cells is the centrosome. A centrosome has two cylindrical centrioles at its core. Each centriole consists of nine sets of three microtubules held together by proteins. The centrioles are positioned at right angles to each other and surrounded by a shapeless protein cloud called the pericentriolar matrix, or pericentriolar material (PCM). To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
02:25
Centrosome Duplication
0 Views •
2021
The primary microtubule organizing center (MTOC) in animal cells is the centrosome. A centrosome has two cylindrical centrioles at its core. Each centriole consists of nine sets of three microtubules held together by proteins. The centrioles are positioned at right angles to each other and surrounded by a shapeless protein cloud called the pericentriolar matrix, or pericentriolar material (PCM). To ensure that each daughter cell receives a centrosome after cell division, centrosome duplication...
02:05
Duplication of Chromatin Structure
0 Views •
2021
The process of chromosome duplication during cell division requires genome-wide disruption and re-assembly of chromatin. The chromatin structure must be accurately inherited, reassembled, and maintained in the daughter cells to ensure lineage propagation. The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...
FAQs
Unequal crossing over creates an extra gene copy during meiosis when the exchange distributes corresponding genetic material unevenly. This mechanism differs from replication errors because it occurs during chromosome exchange rather than during DNA copying. The resulting change can alter the number or arrangement of gene copies in a genome, providing material that may later influence biological traits.
This route begins with messenger RNA, which is reverse-transcribed into a DNA sequence and then inserted into the genome. Unlike unequal crossing over, it does not arise from an uneven exchange during meiosis. The inserted sequence adds gene-derived material at a genomic location, creating another possible source of duplicated information for later evolutionary change.
After duplication, the copies can follow different evolutionary trajectories. One may retain the original function, while the other accumulates mutations that produce a new role or leave it inactive. These contrasting outcomes help explain how duplicated sequences can persist, diverge, and contribute to the formation of gene families over time.
An additional gene copy can change the amount or balance of genetic information available in a genome. Because gene duplication can reshape biological traits, altered copy number may have consequences beyond DNA structure alone. This makes duplicated genes relevant when researchers connect genomic changes with differences in organismal characteristics or biological function.
Gene duplication supplies repeated genetic material that can be retained, modified, or lost. Across evolutionary time, these outcomes can contribute to gene families, functional innovation, and greater genome complexity. Examining duplicated sequences therefore helps researchers connect specific genomic changes with broader patterns of genome evolution rather than treating each gene as an isolated unit.
Duplicated genomic regions and altered gene dosage can contribute to disease, making copy changes important targets for biological investigation. Researchers can examine these features alongside the affected genome to consider how extra or repeated genetic material may influence disease-associated outcomes. This perspective links genome structure with the potential consequences of abnormal gene copy number.