Prevalence Estimates of Selected Gene Variants of the U.S. Population Published

Measuring genetic variation in the U.S. population is important for understanding how individuals and groups vary in disease susceptibility, progression, and outcomes. It is also important for determining the contribution of genetic and environmental factors to human health. In a new study published this month in the American Journal of Epidemiology, CDC’s Office of Public Health Genomics (OPHG) reports allele frequency and genotype prevalence estimates of selected candidate gene variants for a nationally-representative sample of the U.S. population.

A collaboration of researchers from across CDC and the National Cancer Institute (NCI) measured and evaluated 90 variants in 50 candidate genes from DNA collected from 7,159 participants aged 12 years or older in the Third National Health and Nutrition Examination Survey (NHANES III). These variants and genes were selected based on their potential significance to public health. The estimates were calculated by age, sex, and race/ethnicity among non-Hispanic whites, non-Hispanic blacks, and Mexican-Americans. These estimates are available online as summary frequency tables for each gene studied. Access the U.S. Genome Variation Estimates.

The results from this study provide the foundation for a comprehensive databank of human genetic variation in the U.S. that will serve as an important reference for future investigations into the role genes play in disease. Some possible future investigations using these estimates might explore how genes affect population-level risk for disease and how genetic variants might contribute to health disparities.
Public health strategies that address such disparities are more likely to be effective when they are based on a clear understanding of the multiple risk factors (social, environmental, behavioral, and genetic influences) that contribute to health inequities.

Read the article Prevalence in the United States of Selected Candidate Gene Variants: Third National Health and Nutrition Examination Survey (NHANES III), 1991-1994 published in the November issue of the American Journal of Epidemiology.

National Health and Nutrition Examination Survey (NHANES)
NHANES is a program of population-based studies designed to assess the health and nutritional status of adults and children in the United States. NHANES is a major program of the National Center for Health Statistics (NCHS) of the CDC.

During the second phase (1991-1994) of NHANES III, DNA samples were collected. To create a DNA bank, white blood cells were frozen and cell lines were immortalized using Epstein-Barr virus. The DNA bank contains specimens from 7,159 participants aged 12 years or older. It is jointly maintained by NCHS and CDC’s National Center for Environmental Health. Samples from this DNA bank were used to measure the prevalence of selected genetic variants in the U.S. population and to test their association with outcomes and diseases of public health importance. Read more about the NHANES III DNA bank.

NHANES III Collaborative Genomics Project
OPHG established the NHANES III Collaborative Genomics Project in 2002 to measure the prevalence of selected genetic variants of public health significance in a representative sample of the U.S. population and to examine the associations between the selected genetic variants and disease outcomes available in NHANES III.

The NHANES III Genomics Project includes a working group made up of a multidisciplinary team of epidemiologists, geneticists, laboratory scientists, statisticians, and analysts from across CDC, the National Cancer Institute (NCI) and other institutes. The NHANES III working group is currently investigating the associations of these candidate gene variants with outcomes related to asthma, diabetes, cardiovascular disease, infectious disease, lead exposure, osteoporosis, and reproductive health. These studies are currently in progress and are expected to be available beginning in 2009. Learn more about the NHANES III Collaborative Genomics project.

Note: These NHANES III genetic data are not publicly-accessible. These data are available only within the Research Data Center (RDC) at NCHS in Hyattsville, Maryland. Approval from the NCHS Ethics Review Board (ERB) is required before these data can be accessed. More information on how to apply for access is available on the NCHS Web site.