Two new variants with the same substitution at position beta122: Hb Bushey [beta122(GH5)Phe-->Leu] and Hb Casablanca [beta65(E9)lys-->Met; beta122(GH5)Phe-->Leu].
Hb Bushey, found in a Chinese baby and his father, is a new variant with a point mutation leading to the substitution Phe-->Leu at position beta122. Hb Casablanca, found in a family from Morocco, is a further example of a hemoglobin variant that carries two abnormalities in the same chain; the first is identical to that of Hb Bushey and the second to that of Hb J-Antakya [beta65 (E9)Lys-->Met]. Structural abnormalities of both Hbs were determined by protein chemistry methods including electrospray and tandem mass spectrometry. Their stability and oxygen binding properties were found to be identical to those of Hb A. Various mechanisms that may lead to two point mutations in the same chain are reviewed briefly.
Wajcman
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INSERM U 468 and Department of Biochemistry Hôpital Henri Mondor AP-HP, Créteil, France. wajcman@im3.inserm.fr
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Henthorn
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Kister
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Prehu
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Riou
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Promé
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Galactéros
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D019794:2,3-Diphosphoglycerate / Q000494:pharmacology; D000328:Adult; D019943:Amino Acid Substitution; D044466:Asian People / Q000235:genetics; D002851:Chromatography, High Pressure Liquid; D005192:Family Health; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D014644:Genetic Variation; D005914:Globins / Q000737:chemistry / Q000235:genetics; D006455:Hemoglobins, Abnormal / Q000737:chemistry* / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009018:Morocco / Q000208:ethnology; D010100:Oxygen / Q000378:metabolism; D017354:Point Mutation; D006113:United Kingdom
D006455:Hemoglobins, Abnormal; C415471:hemoglobin Bushey; C415472:hemoglobin Casablanca; D019794:2,3-Diphosphoglycerate; D005914:Globins; D010100:Oxygen