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Karyotypic and meiotic evidence for a robertsonian chromosome polymorphism in the lizard Liolaemus fuscus (Tropiduridae, Sauria)

P. Iturra^I; A. Veloso^II; P. Espejo^II; J. Navarro^I

^IDepartamento de Biologia Celular y Genética. Facultad de Medicina, Universidad de Chile, Casilla 70061-7, Santiago, Chile. Phone: 7370081; Fax: 56-02-7373158. Send correspondence to P.I.
^IIDepartamento de Ciencias Ecológicas, Facultad de Ciencias, Universidad de Chile, Santiago, Chile

ABSTRACT

A population chromosome polymorphism due to a single centric fission of pair four in the lizard Liolaemus fuscus (2n=32) from northern Chile, is described. Metaphase II analysis of heterozygote males showed a regular meiotic segregation (97%). This supports hypotheses that centric fission rearrangements are involved in this lizard's karyotypic diversity and that the meiotic effects of fission heterozygotes are nearly neutral in most populations.

Keywords: karyotypic; meiotic; robertsonian chromosome; polymorphism; Liolaemus fuscus.

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