title: Alpha78(EF7)Asn-->Asp is a posttranslational modification in Hb J-Singapore [alpha78(EF7)Asn-->Asp;alpha79(EF8)Ala-->Gly].
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.
authors.affiliation: Department of Haematology, St James's Hospital, Dublin, Ireland.
authors.forename: David A
authors.initials: DA
authors.lastname: O'Brien
authors.forename: Barnaby
authors.initials: B
authors.lastname: Clark
authors.forename: Dilip K
authors.initials: DK
authors.lastname: Rai
mesh_terms: D000328:Adult; D005260:Female; D006448:Hemoglobin J / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D011499:Protein Processing, Post-Translational; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D006448:Hemoglobin J