Genome-wide analysis of the frequency and distribution of crossovers at male and female meiosis in Sinapis alba L. (white mustard)

• Published in: Theoretical and applied genetics Vol. 111; no. 1; pp. 31 - 43
• Main Authors: Nelson, M.N, Nixon, J, Lydiate, D.J
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.06.2005; Berlin Springer Nature B.V
• Subjects: Biological and medical sciences; Chromosome Mapping; Classical genetics, quantitative genetics, hybrids; crossing over; Crossing Over, Genetic - genetics; Fundamental and applied biological sciences. Psychology; gene segregation; Genetic linkage; genetic markers; genetic recombination; Genetics; Genetics of eukaryotes. Biological and molecular evolution; Genome, Plant; germ cells; linkage (genetics); linkage groups; loci; meiosis; Meiosis - genetics; ova; pollen; Polymorphism, Restriction Fragment Length; Pteridophyta, spermatophyta; restriction fragment length polymorphism; Sex Factors; Sinapis - genetics; Sinapis alba; Vegetals; Male; Meiosis; Cruciferae; Dicotyledones; Analysis; Angiospermae; Distribution; Female; Frequency; Genetics; Spermatophyta; Agriculture; Sinapis alba; Genome
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-005-1961-4

We present the first genetic linkage maps of Sinapis alba (white mustard) and a rigorous analysis of sex effects on the frequency and distribution of crossovers at meiosis in this species. Sex-averaged maps representing recombination in two highly heterozygous parents were aligned to give a consensus map consisting of 382 loci defined by restriction fragment length polymorphisms and arranged in 12 linkage groups with no unlinked markers. The loci were distributed in a near-random manner across the genome, and there was little evidence of segregation distortion. From these dense maps, a subset of spaced informative markers was used to establish recombination frequencies assayed separately in male and female gametes and derived from two distinct genetic backgrounds. Analyses of 746 gametes indicated that recombination frequencies were greater in male gametes, with the greatest differences near the ends of linkage groups. Genetic background had a lesser effect on recombination frequencies, with no discernible pattern in the distribution of such differences. The possible causes of sex differences in recombination frequency and the implications for plant breeding are discussed.