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Published on: October 4, 2017
Alpha78(EF7)Asn-->Asp is a posttranslational modification in Hb J-Singapore
David A O'Brien1, Barnaby Clark, Dilip K Rai
1Department of Haematology, St James's Hospital, Dublin, Ireland.
Abstract:
In Hb J-Singapore, the alpha78(EF7)Asn-->Asp and alpha79(EF8)Ala-->Gly substitutions were initially thought to be genetic mutations. Subsequent studies on other similar hemoglobin variants suggested that the Asn-->Asp change was a posttranslational modification. Nevertheless, lack of DNA evidence made it difficult to confirm the deamidation in Hb J-Singapore. We recently encountered a female patient with Hb J-Singapore trait. In this report, we present electrospray mass spectrometry and DNA data to confirm the alpha78(EF7)Asn-->Asp is indeed a posttranslational modification.
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