Evidence for Independent Heritability of the Glycation Gap (Glycosylation Gap) Fraction of HbA1c in Nondiabetic Twins
Response to Nuttall
- Robert M. Cohen, MD1,
- Harold Snieder, PHD23,
- Christopher J. Lindsell, PHD1,
- Huriya Beyan, PHD4,
- Mohammed I. Hawa, BSC4,
- Stuart Blinko, PHD5,
- Raymond Edwards, PHD6 and
- R. David G. Leslie, MD4
- 1Division of Endocrinology, Department of Medicine, Department of Emergency Medicine, General Clinical Research Center, University of Cincinnati, Medical Service, Cincinnati VA Medical Center, Cincinnati, Ohio
- 2Department of Pediatrics, Georgia Prevention Institute, Medical College of Georgia, Augusta, Georgia
- 3Twin Research and Genetic Epidemiology Unit, St. Thomas’ Hospital, London, U.K.
- 4Centre for Diabetes and Metabolic Medicine, Institute of Cell and Molecular Science, St. Bartholomews, London, U.K.
- 5Abbott Murex Biotech (SB), Dartford, U.K.
- 6Royal London Medical School and NETRIA, St. Bartholomews Hospital, London, U.K.
- Address correspondence to Professor David Leslie, Department of Diabetes and Metabolic Medicine, Institute of Cell and Molecular Science, London E1 2AT, U.K. E-mail: r.d.g.leslie{at}qmul.ac.uk
We appreciate Dr. Nuttall (1) drawing our attention back to the considerations raised by his previous work (2). In essence, the suggestion is that one of the sources of variability in A1C, when determined by a charge-based methodology like anion-exchange high-performance liquid chromotography, is that there are other modifications or variants to hemoglobin that could cause the same alterations in charge as glycation and that these are more common than is generally recognized. This leads to the question whether such alterations could explain the finding of heritability …
