Prevalence of B chromosomes in Orthoptera is associated with shape and number of A chromosomes.
Genetica
; 138(11-12): 1181-9, 2010 Dec.
Article
em En
| MEDLINE
| ID: mdl-21052786
ABSTRACT
We analyze the prevalence of B chromosomes in 1,601 species of orthopteran insects where chromosome number and shape are known. B chromosomes have been reported in 191 of these species. Bs are not uniformly distributed among orthopteran superfamilies, with evident hotspots in the Pyrgomorphoidea (32.3% of species carrying Bs), Grylloidea (14.9%), Acridoidea (14.6%) and Tetrigoidea (14.3%). As expected under the theory of centromeric drive, we found a correlation between B chromosome presence and A chromosome shape-Bs are more frequent in karyotypes with more acrocentric A chromosomes. We also found that Bs are less common in species with high chromosome numbers and appear to be most common at the modal chromosome number (2n = 24). Study effort, measured for each genus, was not associated with B prevalence, A chromosome shape or A chromosome number. Our results thus provide support for centromeric drive as an important and prevalent force in the karyotypic evolution of Orthoptera, just as it appears to be in mammals. We suggest that centromeric drive may provide a mechanistic explanation for White's principle of karyotypic orthoselection.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ortópteros
/
Centrômero
/
Cromossomos
/
Cariotipagem
Tipo de estudo:
Prevalence_studies
/
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
Genetica
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos