Sequence diversity in the tetraploid Zea perennis and the closely related diploid Z. diploperennis: insights from four nuclear loci.
Genetics
; 158(1): 401-12, 2001 May.
Article
em En
| MEDLINE
| ID: mdl-11333248
ABSTRACT
Polyploidy has been an extremely common phenomenon in the evolutionary history of angiosperms. Despite this there are few data available to evaluate the effects of polyploidy on genetic diversity and to compare the relative effects of drift and selection in polyploids and related diploids. We investigated DNA sequence diversity at four nuclear loci (adh1, glb1, c1, and waxy) from the tetraploid Zea perennis and the closely related diploid Z. diploperennis. Contrary to expectations, we detected no strong evidence for greater genetic diversity in the tetraploid, or for consistent differences in the effects of either drift or selection between the tetraploid and the diploid. Our failure to find greater genetic diversity in Z. perennis may result from its relatively recent origin or demographic factors associated with its origin. In addition to comparing genetic diversity in the two species, we constructed genealogies to infer the evolutionary origin of Z. perennis. Although these genealogies are equivocal regarding the mode of origin, several aspects of these genealogies support an autotetraploid origin. Consistent with previous molecular data the genealogies do not, however, support the division of Zea into two sections, the section Zea and the section Luxuriantes.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Ploidias
/
Variação Genética
/
Zea mays
Idioma:
En
Revista:
Genetics
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Estados Unidos