skip navigation nih record
Vol. LXI, No. 1
January 9, 2009

previous story

next story


  An international consortium, in search of genetic risk factors for obesity, has identified six new genetic variants associated with body mass index.  
  An international consortium, in search of genetic risk factors for obesity, has identified six new genetic variants associated with body mass index.  

New Genetic Risk Factors Involved in Adult, Childhood Obesity

An international consortium, in search of the genetic risk factors for obesity, has identified six new genetic variants associated with BMI, or body mass index, a measurement that compares height to weight. The results, funded in part by NIH, were published online in the journal Nature Genetics on Dec. 14. The effect of each individual genetic variant was modest and the authors state in the paper that their findings have uncovered only a small fraction of what are probably hundreds of regions in the human genome that are likely to have minor contributions to obesity. The paper estimates that the 1 percent of people harboring the most obesity-causing variants will be an average of 10 pounds heavier than the 1 percent of individuals with the fewest variants, and 4 pounds heavier than a typical person.

The research team tested and compared BMI data and genetic information from more than 32,000 individuals of European ancestry pooled from 15 genome-wide association studies, in the end identifying 35 genetic variants. These genetic variants were further tested for validation in more than 50,000 additional individuals, also of European ancestry. Genetic variants in six genes were shown to be strongly associated with BMI. All six were found to be activated in the central nervous system, specifically the brain and hypothalamus. Prior studies have demonstrated the role of the central nervous system in body weight regulation, including appetite, energy expenditure and other behavioral aspects. The results are consistent with outcomes from family and twin studies, which suggest that genetic factors may account for as much as 40 to 70 percent of BMI variation in the general population.

NCI Launches Tool to Predict Colorectal Cancer Risk

A new online tool for calculating colorectal cancer risk in men and women age 50 or older has been launched, based on a new risk-assessment model developed by researchers at NCI. The tool may assist health care providers and their patients in making informed choices about when and how to screen for colorectal cancer and can be used in designing colorectal cancer screening and prevention trials. An article describing the work appeared online Dec. 29 in the Journal of Clinical Oncology.

Using easily obtainable information (e.g., personal and family medical history, lifestyle behaviors and age), the tool provides an estimate of an individual’s risk of developing colorectal cancer over certain time periods (within 5 years, 10 years, and over the course of a lifetime). This risk-assessment model is the first to provide an absolute risk estimate for colorectal cancer (i.e., the probability of developing colorectal cancer over a given period of time) for the general, non-Hispanic white population age 50 or older in the United States. The tool is available at People using it should consult their health care providers to interpret results. Approximately one in 18 Americans will develop colorectal cancer at some point during his or her lifetime. In 2008, an estimated 148,810 people were diagnosed with colorectal cancer in the United States and another 49,960 will die of the disease.

Common Treatment for Prostatitis Fails

Alfuzosin, a drug commonly prescribed for men with chronic prostatitis, a painful disorder of the prostate and surrounding pelvic area, failed to significantly reduce symptoms in recently diagnosed men who had not been previously treated with this drug, according to a clinical trial sponsored by NIDDK. The study is to be published in the New England Journal of Medicine. Chronic prostatitis, which has no known cause and no uniformly effective therapy, is the most common type of prostatitis seen by physicians. Men with this condition experience pain in the genital and urinary tract areas, lower urinary tract symptoms such as pain in the bladder area and during urination, and sexual problems that can severely affect their quality of life. Population-based surveys estimate that 6 percent to 12 percent of men have prostatitis-like symptoms.

back to top of page