Fig. 3From: A complete duplication of X chromosome resulting in a tricentric isochromosome originated by centromere repositioningHypothetical mechanism of marker formation. a Normal chromosome X. b Crossing-over mechanism between Xp telomere and the centromeric telomere-like sequences. c Paracentric inversion involving the Xp arm that results in a shift of the p end of centromere. d Duplication of the entire X chromosome, that gives rise to an isochromosome XBack to article page