Advertisement

Theoretical and Applied Genetics

, Volume 97, Issue 1–2, pp 293–298 | Cite as

Method for mapping a partial lethal-factor locus on a molecular-marker linkage map of a backcross and doubled-haploid population

  • R. Cheng
  • A. Kleinhofs
  • Y. Ukai

Abstract

 Distorted segregation has been repeatedly observed in various plant species in molecular-marker linkage mapping where distant crosses were made. It may be caused by a partial lethal-factor acting in the filial generations. A method is presented for estimating the recombination values between a partial lethal-factor locus and a linked molecular marker and the relative viability or fertilization ability of zygotes or gametes, respectively affected by the partial lethal factor in backcross (BC) and doubled-haploid (DH) populations using the maximum-likelihood method associated with the expectation maximization (EM) algorithm. The method was applied to segregation data of molecular markers for a population of 150 DH lines developed from the ‘Steptoe’בMorex’ cross in barley. The presence of a partial lethal-factor locus, located on chromosome 4, causing partial selection was suggested. This locus was tightly linked to the ABG500B marker, and the chance of fertilization of female gametes possessing the partial lethal factor was, on average, 59.8% that of a normal one. Two additional partial lethal factors were found on chromosome 5.

Key words Distorted segregation Molecular marker Recombination value Maximum-likelihood method EM algorithm 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • R. Cheng
    • 1
  • A. Kleinhofs
    • 2
  • Y. Ukai
    • 1
  1. 1.Laboratory of Biometrics, Division of Agricultural and Life Sciences, University of Tokyo, Yayoi 1-1-1, Bunkyo, Tokyo 113, Japan Fax: +813-3815-5851 E-mail: cheng@peach.ab.a.u.-tokyo.ac.jp ukai@peach.ab.a.u-tokyo.ac.jpJP
  2. 2.Department of Crop and Soil Sciences, Washington State University, Pullman, WA 99164-6420, USAUS

Personalised recommendations