Genetic Research Brings New Information Referring to Milk and Risk of Renal Cancer

Previous research had induced the idea that drinking milk was increasing the risk of renal cell cancer, but a recent study denies the genetic contribution milk consumption could bring to renal cancer risk.
Lead researcher Nicholas Timpson, Ph.D., is a lecturer in genetic epidemiology at the MRC CAiTE Center in the department of social medicine at the University of Bristol, in the United Kingdom. He said that the data in the study is no concrete evidence that milk drinking should be altered in any way. Timpson also added that lack of reasons to associate milk and renal cell cancer leads to the conclusion that no fear that milk consumption would increase cancer risk is likely to be founded.
The results of the study are published in the May issue of Cancer Epidemiology, Biomarkers & Prevention, which is a journal of the American Association for Cancer Research.
A connection between milk consumption and the risk of renal cell carcinoma was established by early studies, but it is not very clear if this association is only casual or is determined by real facts. Timpson and his colleagues have used a genetic marker to help them clarify this topic.
During four years, starting from 1999, the researchers have conducted a large case-control study in hospitals from four countries situated in Central and Eastern Europe.
Researchers have used observational, genetic and phenotypic information and determined that the genetic variant at the gene MCM6, supposed to be associated with lactose tolerance, may be used as a marker for milk consumption linked to cancer risk.
Adult milk drinkers versus non-milk drinkers present a difference in the odds of renal cell cancer of approximately 35 percent. However, the evaluation of the relationship in a more direct way, based on genetic data, does not reveal any association between milk drinking and renal cancer.
Timpson said that they found evidence for the relationship between renal cancer and milk consumption, but when using genotypes to verify this relationship no corroboration was possible. This fact suggests that the basic findings could be subject to inaccuracies that often affect epidemiological research. According to Timpson, the study needs to be contracted on a larger scale to verify initial findings.
Johanna Lampe, Ph.D., is an editorial board member of Cancer Epidemiology, Biomarkers & Prevention and is not associated with this study. She also is a full member and nutrition scientist in the division of public health sciences at Fred Hutchinson Cancer Research Center in Seattle, Wash. Lampe said that the research demonstrates the complexity of such an evaluation, when it comes to dietary exposure and cancer risk.
According to her, the results of the study invite to caution when interpreting data that indicate an association between certain foods and the risk of a particular form of cancer, as human diet is far too complex and typically involves adherence to dietary patterns related to lifestyle behaviors.