Home

allotetraploid

An allotetraploid is an organism with four sets of chromosomes derived from two different species, formed by interspecific hybridization followed by chromosome doubling. In an initial hybrid between two diploid species, each chromosome set is from a different lineage, often causing sterility because homologous chromosomes fail to pair properly during meiosis. Doubling the chromosome complement creates two complete sets from each parent, enabling pairing within each subgenome and restoring fertility. The resulting organism exhibits disomic inheritance, behaving genetically as two paired chromosome sets.

Allotetraploids are a major class of allopolyploids and often combine traits from both parent species. They

Examples include Brassica napus, an allotetraploid with AACC genomes derived from Brassica rapa (AA) and Brassica

See also polyploidy, allopolyploidy.

can
display
heterosis
and
novel
phenotypes,
and
their
genomes
may
undergo
rapid
stabilization
after
formation,
including
gene
expression
changes
and
epigenetic
remodeling
that
can
lead
to
subgenome
dominance.
oleracea
(CC).
In
cotton,
several
cultivated
species
such
as
Gossypium
hirsutum
and
Gossypium
barbadense
are
allotetraploids
with
A
and
D
genomes,
formed
from
ancestral
A-
and
D-genome
lineages.
Tragopogon
miscellus
and
related
species
are
classic
natural
allotetraploids
formed
in
the
wild
from
hybridization
of
other
Tragopogon
species.