Haemochromatosis gene mutations Cys282Tyr and His63Asp are not increased in Type 2 diabetic patients compared with the Canterbury (New Zealand) general population

• Published in: Diabetes research and clinical practice Vol. 43; no. 3; pp. 199 - 203
• Main Authors: Florkowski, Chris M., George, Peter M., Willis, Jinny A., Stott, Marion K., Burt, Michael J., Upton, Jeff D., Nesbit, Jeff, Walmsley, Trevor A., Scott, Russell S.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 01-03-1999; Elsevier Science
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Colorimetry; Diabetes Mellitus, Type 2 - genetics; Diabetes. Impaired glucose tolerance; DNA - chemistry; DNA Primers - chemistry; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Female; Ferritins - blood; Genotype; Haemochromatosis gene; Hemochromatosis - epidemiology; Hemochromatosis - genetics; Humans; Immunoenzyme Techniques; Iron - blood; Iron - metabolism; Iron Overload - genetics; Male; Medical sciences; Middle Aged; Mutation, Missense; Nephelometry and Turbidimetry; New Zealand - epidemiology; Phlebotomy; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Transferrin - analysis; Tropical medicine; Type 2 diabetes mellitus; New Zealand; Oceania; Type 2 diabetes mellitus; Haemochromatosis gene; Endocrinopathy; Human; Transferrin; Hemochromatosis; Prevalence; Ferritin; Metabolic diseases; Iron; Enzymopathy; Non insulin dependent diabetes; Genetic determinism; Sensitivity; Specificity; Restriction fragment length polymorphism; Gene; Etiology; Genetics; Adult; Mutation; Molecular biology; Elderly; Comparative study
• ISSN: 0168-8227; 1872-8227
• DOI: 10.1016/S0168-8227(98)00129-6

Genetic predisposition to haemochromatosis may be an important aetiological factor in some cases of Type 2 diabetes. Our aim was therefore to test the hypothesis that the haemochromatosis gene mutations Cys282Tyr and His63Asp are more prevalent in Type 2 diabetic patients compared with the Canterbury, New Zealand general population. We studied 230 consecutive patients referred to the Diabetes Services with age ≥30 years and considered to have Type 2 diabetes. DNA was extracted from whole blood and amplified by polymerase chain reaction prior to restriction fragment length polymorphism analysis. The frequency of the mutations was compared with that observed previously in 1064 subjects from the Canterbury general population by
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2 testing. Iron was measured by a colorimetric method, transferrin by rate nephelometry and ferritin by immunoassay. There were 2/230 (0.8%) Cys282Tyr homozygous subjects in the diabetic group compared with 5/1064 (0.5%) NS in the general population. Although there was a trend to lower incidence of Cys282Tyr heterozygosity in the diabetic group, there was no significant difference for any of the six genotype frequencies between the two groups. Haemochromatosis gene mutations Cys282Tyr and His63Asp are therefore not increased in Type 2 diabetics compared with the general population. Transferrin saturation was a sensitive marker (100%) of genetic haemochromatosis, although ferritin had low specificity (77.8%). Genetic susceptibility to haemochromatosis is not an important aetiological factor for diabetes, and targeted screening of diabetic patients for haemochromatosis is not indicated.