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Molecular cloning of exons II and IIIof the a-globin major gene from Odontophrynus americanus 2n and 4n(Amphibia, Anura)
Maria Dolores P. AcedoI; Gláucia Paranhos-BaccalàII; Claudio D. DenoyaIII; Itamar R.G. RuizIV
IDepartamento de Biologia Geral, ICB, UFMG, Caixa Postal 486, 31270-901 Belo Horizonte, MG, Brasil. Send correspondence to M.D.P.A.
IIUMR 103, Unité Mixte CNRS-bioMérieux, Lyon, France.
IIIPfizer Inc., Groton, USA.
IVLaboratório de Genética, Instituto Butantan, SP, Brasil.
ABSTRACT
The a-globin major genes from diploid and tetraploid Odontophrynus americanus were studied using PCR-based technology. The cloned and sequenced amplified fragments were shown to contain most of the exon II sequences as well as the whole exon III sequence of the a-globin gene. Unexpectedly, intron 2 was entirely absent in the amplified fragments of both 2n and 4n origin. High conservation was observed among the obtained sequences when compared to corresponding sequences from human and Xenopus laevis origin. The possibility that these sequences might be pseudogenes is raised.
Keywords: cloning; exons; a-globin; Odontophrynus; Anura.
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