Genetics, Vol. 159, 1339-1350, November 2001, Copyright © 2001

A Multivalent Pairing Model of Linkage Analysis in Autotetraploids

Samuel S. Wua, Rongling Wua, Chang-Xing Maa,b, Zhao-Bang Zengc, Mark C. K. Yanga, and George Casellaa
a Department of Statistics, University of Florida, Gainesville, Florida 32611,
b Department of Statistics, Nankai University, Tianjin 300071, People's Republic of China
c Department of Statistics, North Carolina State University, Raleigh, North Carolina 27695

Corresponding author: Samuel S. Wu, Division of Biostatistics, P. O. Box 100212, University of Florida, Gainesville, FL 32610., samwu{at}biostat.ufl.edu (E-mail)

Communicating editor: J. B. WALSH

Polyploidy has been recognized as an important step in the evolutionary diversification of flowering plants and may have a significant impact on plant breeding. Statistical analyses for linkage mapping in polyploid species can be difficult due to considerable complexities in polysomic inheritance. In this article, we develop a novel statistical method for linkage analysis of polymorphic markers in a full-sib family of autotetraploids. This method is established on multivalent pairings of homologous chromosomes at meiosis and can provide a simultaneous maximum-likelihood estimation of the double reduction frequencies of and recombination fraction between two markers. The EM algorithm is implemented to provide a tractable way for estimating relative proportions of different modes of gamete formation that generate identical gamete genotypes due to multivalent pairings. Extensive simulation studies were performed to demonstrate the statistical properties of this method. The implications of the new method for understanding the genome structure and organization of polyploid species are discussed.





This article has been cited by other articles:


Home page
GeneticsHome page
Z. W. Luo and Z. Zhang
Commentary on Wu and Ma
Genetics, December 1, 2005; 171(4): 2149 - 2150.
[Full Text] [PDF]


Home page
GeneticsHome page
R. Wu and C.-X. Ma
A General Framework for Statistical Linkage Analysis in Multivalent Tetraploids
Genetics, June 1, 2005; 170(2): 899 - 907.
[Abstract] [Full Text] [PDF]


Home page
GeneticsHome page
J. E. Bradshaw, B. Pande, G. J. Bryan, C. A. Hackett, K. McLean, H. E. Stewart, and R. Waugh
Interval Mapping of Quantitative Trait Loci for Resistance to Late Blight [Phytophthora infestans (Mont.) de Bary], Height and Maturity in a Tetraploid Population of Potato (Solanum tuberosum subsp. tuberosum)
Genetics, October 1, 2004; 168(2): 983 - 995.
[Abstract] [Full Text] [PDF]


Home page
Proc. Natl. Acad. Sci. USAHome page
Z. W. Luo, R. M. Zhang, and M. J. Kearsey
Theoretical basis for genetic linkage analysis in autotetraploid species
PNAS, May 4, 2004; 101(18): 7040 - 7045.
[Abstract] [Full Text] [PDF]


Home page
Crop Sci.Home page
R. G. Fjellstrom, J. J. Steiner, and P. R. Beuselinck
Tetrasomic Linkage Mapping of RFLP, PCR, and Isozyme Loci in Lotus corniculatus L.
Crop Sci., May 1, 2003; 43(3): 1006 - 1020.
[Abstract] [Full Text] [PDF]


Home page
Genome ResHome page
C.-X. Ma, G. Casella, Z.-J. Shen, T. C. Osborn, and R. Wu
A Unified Framework for Mapping Quantitative Trait Loci in Bivalent Tetraploids Using Single-dose Restriction Fragments: A Case Study from Alfalfa
Genome Res., December 1, 2002; 12(12): 1974 - 1981.
[Abstract] [Full Text] [PDF]