Allelic segregation and independent assortment in T. brucei crosses: proof that the genetic system is Mendelian and involves meiosis

MacLeod, A. , Tweedie, A., McLellan, S., Taylor, S., Cooper, A., Sweeney, L., Turner, C.M.R. and Tait, A. (2005) Allelic segregation and independent assortment in T. brucei crosses: proof that the genetic system is Mendelian and involves meiosis. Molecular and Biochemical Parasitology, 143(1), pp. 12-19. (doi: 10.1016/j.molbiopara.2005.04.009)

Abstract

The genetic system on Trypanosoma brucei has been analysed by generating large numbers of independent progeny clones from two crosses, one between two cloned isolates of Trypanosoma brucei brucei and one between cloned isolates of T. b. brucei and Trypanosoma brucei gambiense, Type 2. Micro and minisatellite markers (located on each of the 11 megabase housekeeping chromosomes) were identified, that are heterozygous in one or more of the parental strains and the segregation of alleles at each locus was then determined in each of the progeny clones. The results unequivocally show that alleles segregate in the predicted ratios and that alleles at loci on different chromosomes segregate independently. These data provide statistically robust proof that the genetic system is Mendelian and that meiosis occurs. Segregation distortion is observed with the minisatellite locus located on chromosome I of T. b. gambiense Type 2 and neighboring markers, but analysis of markers further along this chromosome did not show distortion leading to the conclusion that this is due to selection acting on one part of this chromosome. The results obtained are discussed in relation to previously proposed models of mating and support the occurrence of meiosis to form haploid gametes that then fuse to form the diploid progeny in a single round of mating.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: MacLeod, Professor Annette and Taylor, Dr Sonya
• Authors: MacLeod, A., Tweedie, A., McLellan, S., Taylor, S., Cooper, A., Sweeney, L., Turner, C.M.R., and Tait, A.
• Subjects: Q Science > QR Microbiology > QR355 Virology
• College/School: College of Medical Veterinary and Life Sciences; College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Molecular and Biochemical Parasitology
• Publisher: Elsevier BV
• ISSN: 0166-6851
• ISSN (Online): 1872-9428
• Copyright Holders: Copyright © 2005 Elsevier
• First Published: First published in Molecular and Biochemical Parasitology 143(1):12-19
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher