Format

Send to

Choose Destination
Genetics. 2005 Feb;169(2):967-79. Epub 2004 Nov 1.

Detection of chromosomal rearrangements derived from homologous recombination in four mapping populations of Brassica napus L.

Author information

1
Department of Agronomy, University of Wisconsin, Madison, Wisconsin 53706, USA.

Abstract

Genetic maps of Brassica napus were constructed from four segregating populations of doubled haploid lines. Each mapping population had the same male parent and used the same set of RFLP probes, facilitating the construction of a consensus map. Chromosomal rearrangements were identified in each population by molecular marker analysis and were classified as de novo homologous nonreciprocal transpositions (HNRTs), preexisting HNRTs, and homologous reciprocal transpositions (HRTs). Ninety-nine de novo HNRTs were identified by the presence of a few lines having duplication of a chromosomal region and loss of the corresponding homologous region. These de novo HNRTs were more prevalent in one population that had a resynthesized B. napus as a parent. Preexisting HNRTs were identified by fragment duplication or fragment loss in many DH lines due to the segregation of HNRTs preexisting in one of the parents. Nine preexisting HNRTs were identified in the three populations involving natural B. napus parents, which likely originated from previous homologous exchanges. The male parent had a previously described HRT between N7 and N16, which segregated in each population. These data suggest that chromosomal rearrangements caused by homologous recombination are widespread in B. napus. The effects of these rearrangements on allelic and phenotypic diversity are discussed.

PMID:
15520255
PMCID:
PMC1449096
DOI:
10.1534/genetics.104.033209
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center