Hemoglobin Lincoln Park: a betadelta fusion (anti-Lepore) variant with an amino acid deletion in the delta chain-derived segment.
1978; National Academy of Sciences; Volume: 75; Issue: 3 Linguagem: Inglês
10.1073/pnas.75.3.1475
ISSN1091-6490
AutoresGeorge R. Honig, Mir Shamsuddin, R. G. Mason, LN Vida,
Tópico(s)Iron Metabolism and Disorders
ResumoAn electrophoretically slow-moving hemoglobin variant was identified in three members of a family originating from Southern Mexico. The variant, Hb Lincoln Park, made up approximately 14% of the total hemoglobin and appeared to have normal stability and functional properties. None of the individuals in whom the abnormal hemoglobin was present was anemic, but each had a mildly elevated reticulocyte count. Structural data suggest that the non-alpha chain of Hb Lincoln Park represents a betadelta gene-fusion product, with normal beta chain structure of the amino-terminal portion of the chain and delta sequences subsequently, the crossover point occurring between animo acid residues 22 and 50. An additional abnormality is the deletion of valine-137, a component of the delta gene-derived segment of the betadelta chain. To account for the development of this abnormal globin chain, a series of intergenic crossovers is proposed; the first, a nonhomologous crossover between the beta and delta genes, presumably gave rise to the betadelta fusion gene; two additional crossovers, one of them unequal, may then have occurred between the same beta and delta genes to produce the amino acid deletion.
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