New Genetic Clues in Cancer Survival, Longevity and Substance Abuse

Taiwan scientists have learned that a simple test of five genes aimed at lung cancer patients can help predict their chances of recovery. The new test can help patients and their physicians decide on cancer treatments such as chemotherapy or other options. Lung cancer is a particularly deadly cancer and is the world's top cancer killer. About 175,000 new cases and 162,000 deaths from lung cancer occur in the United States each year. Similar genetic tests are now being done for patients with breast cancer and lymphoma.

The widespread use of this test is still years away as more experimental studies must be conducted. It is already proving to be extremely promising for use in everyday hospital settings instead of just being done by people with special genetics training.

Dr. David Johnson, a cancer specialist at Vanderbilt University, and former president of the world's largest group of cancer specialists feels this test will be extremely helpful and the understanding of genetic signatures may help to decide which patients need aggressive treatment and which patients may not even need treatment at all. He goes on to say that it will pinpoint those patients who may not respond to current drugs and would do better with trying experimental therapies.

The current staging system for lung cancer patients is imprecise and old-fashioned, and tells physicians nothing close to what the new genetic test can. Some patients in the early stages of lung cancer have such a low risk of recurrence that chemotherapy treatment gives them only slightly better odds. Other patients have aggressive tumors that prove fatal even after very early discovery and aggressive treatment. At present, there is no way to tell these patients apart. The Taiwan test gives a much better way to sort low and high risk patients.

GENES TIED TO LONGEVITY AND COGNITIVE FUNCTION

A gene variant has been found that seems to be linked to living a very long life--to 90 and beyond. The gene also seems to preserve the ability to think clearly. According to scientists at the Albert Einstein College of Medicine at Yeshiva University, they have found that elderly subjects 95 and older who possessed the gene variant were twice as likely to have good brain function based on a standard test of cognitive function.

The term "genetic variation" (gene variant) is used to describe differences in the sequence of DNA among individuals. Genetic variation plays a role in whether a person has a higher or lower rate of getting particular diseases.

Previously, in other studies, this gene variant showed that it helped people live exceptionally long lives and the gene apparently can be passed from generation to generation. The gene variant appears to alter the Cholesterol Ester Protein which affects the size of "good" HDL cholesterol and "bad" LDL cholesterol which are packaged into lipoprotein particles. Scientists believe that larger cholesterol particles are less likely to lodge in and clog blood vessels. This means a lower risk of heart attacks and strokes which may explain the unusual long lives of these individuals.

The findings of this study also suggests that the gene variant protects the cognitive integrity of the brain either through the same 'anti-clotting' theory that prevents heart attacks and strokes, or perhaps due to an independent protective mechanism that is yet to be known.

GENES MAY HELP IDENTIFY PEOPLE AT RISK FOR SUBSTANCE ABUSE

Researchers at the National Institute on Drug Abuse (NIDA) and National Institutes of Health, have recently completed the most comprehensive scan ever done, that can identify the human genome that predicts people most at risk for developing alcoholism. This study represents the first time genomic technology has been used to comprehensively identify genes linked to substance abuse. The term "genome" refers to the total genetic information of a particular organism. The normal human geonome consists of about 3 billion pairs of DNA in each set of chromosomes from one parent.

From previous studies, we know that alcoholism runs in families; but the new research has given the most extensive catalog yet of the genetic variations that may help contribute to the hereditary nature of alcoholism. These new tools can help us understand more about the physiological foundations of addiction.