Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6 Pt 1
pubmed:dateCreated
1998-6-16
pubmed:abstractText
Irreversible glycation of the hemoglobin A0 (HbA0) beta chain leads to the production of HbA1C, which can be used to monitor long-term blood glucose control in patients with diabetes mellitus. HbA1C is less positively charged than nonglycated HbA0, and this decrease in charge is the basis of ion-exchange and electrophoretic methods that measure HbA1C. We recently identified a sample that appeared to contain 46% HbA1C by an automated ion-exchange HPLC method (Bio-Rad Variant) but only 3.8% by an immunoinhibition latex agglutination method. A combination of traditional and mass spectrometric protein analysis and genomic DNA analysis of the Hb beta chain and genes revealed that the patient was heterozygotic for Hb-Raleigh, a variant containing a valine-->alanine substitution at position 1 of the beta chain. The amino-terminal alanine in this variant Hb is posttranslationally modified by acetylation, leading to a charge difference similar to glycation and making the behavior of HbA1C and Hb Raleigh virtually identical in the ion-exchange HPLC method. This observation suggests that it is important to confirm HbA1C values in excess of 15%, especially if they are not consistent with the clinical picture, by an independent HbA1C method such as immunoassay or boronic acid affinity chromatography. However, for this particular variant Hb, even these latter methods might be misleading, because the acetylated N-terminal amino acid of the Hb-Raleigh beta chain cannot be glycated.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0009-9147
pubmed:author
pubmed:issnType
Print
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1296-301
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:9625056-Aged, pubmed-meshheading:9625056-Alanine, pubmed-meshheading:9625056-Amino Acid Substitution, pubmed-meshheading:9625056-Autoanalysis, pubmed-meshheading:9625056-Chromatography, High Pressure Liquid, pubmed-meshheading:9625056-Chromatography, Ion Exchange, pubmed-meshheading:9625056-Chromatography, Liquid, pubmed-meshheading:9625056-Diabetes Complications, pubmed-meshheading:9625056-Diabetes Mellitus, pubmed-meshheading:9625056-Electrophoresis, Agar Gel, pubmed-meshheading:9625056-False Positive Reactions, pubmed-meshheading:9625056-Hemoglobin A, Glycosylated, pubmed-meshheading:9625056-Hemoglobins, Abnormal, pubmed-meshheading:9625056-Humans, pubmed-meshheading:9625056-Isoelectric Focusing, pubmed-meshheading:9625056-Kidney Failure, Chronic, pubmed-meshheading:9625056-Male, pubmed-meshheading:9625056-Mass Spectrometry, pubmed-meshheading:9625056-Mutation, pubmed-meshheading:9625056-Polymerase Chain Reaction
pubmed:year
1998
pubmed:articleTitle
Hemoglobin Raleigh as the cause of a falsely increased hemoglobin A1C in an automated ion-exchange HPLC method.
pubmed:affiliation
Washington University School of Medicine, Division of Laboratory Medicine, St. Louis, MO 63110, USA.
pubmed:publicationType
Journal Article, Comparative Study