Ospring x 100 measuring recombinaon between two loci

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: X X X EVENTUALLY, THE MOST FIT GENOMES IN THE ASEXUAL POPULATION HAVE ONE DELETERIOUS MUTATION (MANY HAVE TWO OR MORE) X Popula*on Popula*on thinking: recombina*on ecombina*on Population without recombination (ASEXUAL) Population with recombination (SEXUAL) XX XX X X XX X X X X X X XX X X X X X X X X XX X X X XX XX X X XX X X THIS PROCESS WAS THEORIZED IN 1932 BY H.G. MULLER, ONE OF THE FOUNDERS OF MODERN GENETICS; became called “Muller’s Ratchet” X scoring recombina*on between two loci •  meiosis in a AB/ab double heterozygote –  remember that if A and B are on different chromosomes or unlinked (physically far away) on same chromosome •  independent assortment –  independent assortment = the highest recombina*on rate possible between two loci •  50% recombina*on rate why 50% is the max •  A = originally with B in the parental P genera*on •  in the gametes of the F1 half the A alleles will s*ll be with B, the other half will be with b –  AB = parentals –  Ab = (one class of) recombinants more generally •  •  •  •  •  •  gametes produced by F1 in a dihybrid cross: AB = parental = 25% ab = parental = 25% Ab = recombinant= 25% aB = parental = 25% ignoring the other parent of the F2: half the progeny are parental genotype, half the progeny are recombinant genotype calcula*ng recombina*on rate •  recomb rate = # Recombinants divided by the total number of offspring •  as a percentage •  (# Recombinants)/(Total offspring) X 100 measuring recombina*on between two loci “two point cross” •  in model species usually measure in one parent –  rates vary between males...
View Full Document

This document was uploaded on 02/27/2014.

Ask a homework question - tutors are online