NEW YORK (Reuters Health) - Homozygosity for the C282Y mutation in the HFE gene, which has been linked to hemochromatosis, is largely confined to whites, new research suggests. As such, genetic screening for this mutation should probably be confined to white populations.
“There was certainly a lot of good data on how common the C282Y mutation is among whites, so I don’t think our main finding is surprising,” study co-author Dr. David M. Reboussin, from Wake Forest University in Winston-Salem, North Carolina, told Reuters Health. Still, “there really hasn’t been a large study to look at these genotype frequencies in North America -- a lot of the data has come from Australia or Scandinavia.”
One surprising finding did, however, emerge from the analysis: despite having the lowest rates of C282Y mutations, Pacific Islanders and Asians had the highest serum ferritin levels.
“That was a big surprise -- it was certainly the one result that nobody expected,” Dr. Reboussin said. These ethnic groups may have unknown mutations in HFE or other genes that are associated with elevated iron levels, he added. “However, the magnitude of the increase suggests that other causes are also at play, such as diet or environmental factors.”
The Hemochromatosis and Iron Overload Screening (HEIRS) study, which is reported in The New England Journal of Medicine for April 28, involved 99,711 subjects who were recruited from primary care practices and blood-drawing laboratories.
A total of 299 subjects were homozygous for the C282Y mutation, the authors note. The estimated prevalence of this genotype was 0.44% in whites, 0.11% in Native Americans, 0.027% in Hispanics, 0.014% in blacks, 0.012% in Pacific Islanders, and 0.000039% in Asians.
Most subjects who were homozygous for the C282Y mutation had elevations in serum ferritin levels and transferrin saturation, the authors point out. Among men, C282Y homozygosity and compound heterozygosity was associated with an elevated risk of liver disease compared with the absence of HFE mutations.
“One implication from this study is that the rate of C282Y homozygotes in minority ethnic groups is so low that I think it will be hard to justify screening in these groups,” Dr. Reboussin said. “In terms of a more comprehensive set of screening guidelines, I think we’ll need to wait until we get the later phases of the data analyzed.”
The release of these findings coincides with a report issued yesterday showing that genetic screening for hemochromatosis can be successfully applied in the workplace setting with high satisfaction rates (see Reuters Health report April 26, 2005).
Source: N Engl J Med 2005;352:1769-1778. [ Google search on this article ]
MeSH Headings:Community Health Services: Data Collection: Diagnosis: Diagnostic Services: Environment and Public Health: Epidemiologic Methods: Health Care Facilities, Manpower, and Services: Genetic Screening: Health: Health Occupations: Health Services: Health Services Administration: Health Surveys: Information Science: Mass Screening: Medicine: Investigative Techniques: Population Characteristics: Preventive Health Services: Preventive Medicine: Public Health: Quality of Health Care: Specialties, Medical: Clinical Medicine: Public Health Practice: Health Care Quality, Access, and Evaluation: Health Care Evaluation Mechanisms: Diagnostic Techniques and Procedures: Analytical, Diagnostic and Therapeutic Techniques and Equipment: Biological Sciences: Health Care: Information ScienceCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
