What is the difference between Autopolyploidy and Allopolyploidy? Autopolyploidy arises by the fusion of gametes of the same species;. Allopolyploidy. Polyploidy is a condition in which an organism has more than two complete sets of chromosomes in every cell (i.e. > diploid). Autopolyploidy. Polyploidy is the state of a cell or organism having more than two paired ( homologous) sets of Autopolyploidy; Allopolyploidy; Paleopolyploidy; Karyotype; Homoeologous chromosomes. 7 Bacteria; 8 Archaea; 9 See also.

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An allopolyploid cell can undergo meiosis. There are also two distinct phenotypes in triploid placentas and fetuses that are dependent on the origin of the extra haploid set.

Speciation by polyploidy has become a popular topic in the scientific community. In some cases, survival past birth may be extended if there is mixoploidy with both a diploid and a triploid cell population present.

Phylogenetics for allopolyploids

If, however, the duplicated chromosomes are homoeologous partially homologous and result strictly from bivalent homologous chromosomes then these are called disomic polyploids. Although the replication and transcription of DNA is highly standardized in eukaryotesthe same autoolyploidy be said for their karotypes, which are highly variable between species in chromosome number and in detailed organization despite allopllyploidy constructed out of the same macromolecules.

Autopolyploidy refers to a type of polyploidy where allopolhploidy chromosome complement consists of more than two copies of homologous chromosomes. Allopolyploids and autopolyploids are crucial for the diversification of groups and present the opportunity to suppress lethal recessive properties.


This means they possess two sets of chromosomes. It combines sought-after characteristics of the parents, but the initial hybrids are sterile. Durum wheat contains two sets of chromosomes derived from Triticum urartu and two sets of chromosomes derived from Aegilops speltoides. Azotobacter vinelandii can contain up to 80 chromosome copies per cell.

This is is an example of somatic doubling.

Annual Review nad Ecology and Systematics. Autopolyploids are polyploids with multiple chromosome sets derived from a single taxon. Species whose cells do not have nuclei, that is, prokaryotesmay be polyploid, as seen in the large bacterium Epulopiscium fishelsoni.


Some crops are found in a variety of ploidies: If the duplicated chromosomes are completely homologous and result from multivalent or random bivalent segregation during meiosis, these are called polysomic polyploids. The nondisjunction of chromosomes can occur in both mitosis and meiosis.

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Retrieved 9 July Sympatric speciation commonly occurs in wheat, which is a type of autopklyploidy. However polyploids species with doubled or other multiples of genomes compared to close relatives are common in plants, and also occur in animals and fungi.

Differences between Autopolyploidy and Allopolyploidy

For some reason some groups tolerate, some strive on while others are strictly against polyploidization. The mule which is produced by the mating of a male donkey with a female horse is an example auropolyploidy a hybrid.

aytopolyploidy In the descriptions above, the processes are described in terms of a single individual producing a new species all by itself. Retrieved from ” https: The result of this is that the resulting cells have tetraploid chromosomes. In an ironic twist, mitosis and meiosis can also be affected negatively when polyploid cells enter cell division.


In the former case, unreduced gametes from each diploid taxa — or reduced gametes from two autotetraploid taxa — combine to form allopolyploid offspring. However allkpolyploidy generated from interploidy crossessuch as between polyploids and their parent species, usually suffer from aberrant endosperm development which impairs their viability, [37] [38] thus contributing to polyploid speciation.

These organisms are called diploids 2n.

As in autopolyploidy, this primarily occurs through the fusion of unreduced 2 n gametes, which can take place before or after hybridization. Diandry is mostly caused by reduplication of the paternal haploid set from a single sperm, but may also be the consequence of dispermic two sperm fertilization of the egg.

For example, many seedless fruit qutopolyploidy are seedless as a result of polyploidy.

Colchicine dissolves spindle fibers which are responsible for pulling apart the sister chromatids so after they align in preparation for the alloppolyploidy splitting to two daughter cells. One can even argue that it has worse consequences in autoploids than in diploids.

This may produce an unbalanced number of chromosomes in the zygote.