Smoke Signals August 1990 Page 9 HEALTH Facts About AIDS, Hepatitis What is AIDS? AIDS stands for acquired immune deficiency syn drome. It's a disease in which the body's immune system breaks down. The immune system fights off infections and certain other diseases. Because the system fails, a person with AIDS develops a variety of life threatening illnesses. . AIDS is Caused by HTV Infection AIDS is caused by the virus called the immunodefi ciency virus, or HIV. A virus is a small germ that can cause disease. If HIV enters your bloodstream, you may become infected with HIV. A special blood test can detect HIV infection. A person who is infected can infect others, even if no symptoms are present. You cannot tell by looking at someone whether he or she is infected with HIV. An infected person can appear completely healthy. Some Disturbing Facts Surveys have found that: The average age for a boy in the United States to have sexual intercourse for the first time is IS and a half. The average age for a girl is 16. It is estimated that 2.5 million teens are infected with sexually transmitted diseases (venereal disease) each year. AIDS is sexually transmitted. Sixty percent of all American high school seniors have used illegal drugs. Some of these drugs are injected. The virus that causes AIDS is spread through the sharing of IV drug needles or syringes. What is Hepatitis? Hepatitis is an injury to the liver which can be caused by many things including bacteria, drugs and alcohol. The different types of hepatitis common in Alaska are type A and B, and non-A and non-B. . .Hepatitis A The hepatitis A virus is passed from the infected person's stool to a non-infected person's mouth, usually through food or drink. The water you drink can have hepatitis A if your water supply has been contaminated by someone who has the virus. It takes two weeks to two months for a person to get sick with hepatitis A after the virus enters the body. Hepatitis B The hepatitis B virus is present in large amounts in blood, semen and the fluids in a woman's period. It is found in smaller amounts in other body fluids also. It is not in stools. An infected person can pass hepatitis B to his or her partner. A pregnant mother with hepatitis B can pass it to her baby. t NEW YORK - Men who use cocaine may be harming their fertility, say researchers who suggest that may help explain why some couples have trouble conceiving a child. In a study of men from couples consulting a fertility clinic, cocaine use was associated with low sperm counts and other problems that can reduce a man's fertility, researchers said. Analysis suggested the apparent effect of cocaine may disappear after the drug use stops, study co-author Michael Bracken, professor of epidemiology, obstetrics and gynecology at Yale University, said Tuesday. The Gene and the Bottle Scientists link alcoholism to a flawed bit of DNA Scientists have long suspected that a tendency to drink too much is in some part hereditary. Children of alcoholics are not only more likely than others to become problem drinkers themselves; studies have shown that they share distinctive brain-wave patterns, and that they're slower than people with nonalcoholic parents to feel the effects of a given dose of booze. These and other findings- such as the fact that rats can be bred cither to crave or to shun alcohol-all suggest that something in an individual's genetic makeup can place him at risk. The question is, what? Last week, for the first time, medical researchers unveiled what looks like a partial answer. Their suspect: a gene that affects the brain's handling of dopamine, one of the chemicals involved in the body's response to alcohol. Writing in the Journal of the American Medical Association, Kenneth Blum of the University of Texas, San Antonio, and Dr. Ernest Noble of UCLA reported that an aberrant form of the so called dpamine D2 receptor gene was strongly associated with alcoholism in the small group of people they studied. The finding could lead to radical new strategies for preventing and treating drinking problems, but it won't yield a complete explanation of why people become alcoholics. Even if larger studies confirm the role of the D2 receptor gene, it will remain but one piece in a large and complex . puzzle. Blum and Noble's study was based on genetic analysis of tissue samples from 70 cadaver brains, half of which had belonged to severe alcoholics. Noble and his col leagues in Los Angeles compiled extensive medical records on the donors and sent the tissue samples to Texas, identified only by code numbers. Blum's team then tested each sample for the aberrant form-thc so called a-1 allele-of the dopamine D2 receptor gene. When the genetic analysis and the clinical histories where combined, a striking pattern emerged: the a-1 allele showed up in 69 percent of the alcoholics' tissue samples but in just 20 percent of the samples drawn from nonalcoholics. Among the 70 subjects, every carrier of the suspect gene had 77 percent chance of being an alcoholic;each noncarrier had a 72 percent chance of not being an alcoholic. No one knows how this genetic aberration might propel people toward drunkennessj'Blum and Noble suspect it may foster an appetite for alcohol and other drugs by suppressing dopamine activity. The dopamine D2 receptor gene directs the construction of tiny portals on surfaces of neurons. In a normal brain, those portals absorbdopamine as its released by neighboring cells. If the a-1 allele produces defective portals, Noble specu- Cocaine May Hamper Fertility But a specialist in male infertility cautioned that the study does not show that cocaine use caused infertility in the men. "This is provocative but by no means evidence of cause and effect," Richard Sherins of the Genetics and IVF Institute of Fairfax, Va. said. The study included 40 men with low sperm counts, 77 who had sperm with low motility, which essentially means too' few sperm were swimming correctly, and 75 who had high concentrations of abnormally shaped sperm. Each of these problems can contribute to infertility. Cocaine use by these 192 men was compared to that of lates, then carriers of that allele may end up with a chronic dopamine defect-and an inordinance fondness for substances that stimulate production of the chemical. If a simple blood test could be developed to identify children who carry this and other troublesome genes, he reasons, those kids could be taught to handle intoxicants with special care. Future drugs might even let erstwhil substance abusers adjust their dopamine levels safely. For the moment.this is all a fantasy. Blum and Noble concede that the aberrant gene is not yet "ready to be used as a diagnostic marker for the risk of alcoholism." There is no guarantee it ever will be. For one thing, the current study involed only 35 of the nations's estimated 18 million alcoholics. Until larger studies produce similar results, the possibility will remain that the corre lation between the gene and the condition was just a statistical fluke. Even if the correlation holds, the question of how paticular genes are related to people'sdrinking behavior will remain wide open. As Dr. Enoch Gordis and his colleagues at the Na tional Institute on Alcoholism note a commentary on the new study, no one knows whether these genes are going to be specific for alcoholism or be of more general influence on affect, appetite, personality or behavior." Unmet appetites: Even if future research confirmed that the a-1 allele interferes with dopamine metabolism, causing a craving for alcohol, we would be far from understanding the alcoholic's self-destructive behavior. Everyone lives with unmet physical appetites, notes philosopher Herbert Fingarette, the author of "Heavy Drinking: The Myth of Alcoholism as a Disease." There's nothing in the dopamine theory to explain why one person responds irrationally while the next person doesn't. Blum and Noble's own study showed that 23 percent of those with the a-1 allele didn't become drunks, and that 28 percent of the noncarriers did. Likewise, the sexes are at equal risk of inheriting the suspect gene, yet American men suffer more than five times as much alcoholism as women. Blum and Noble gladly concede that social factors can override genetic predispositions. That's why they're so optimistic about the possibility of warning carriers of the heightened risk they face. Whether children should be branded "at risk" of a behavioral problem on the basis of genetic tests is debatable. But that debate is a long way off. The more immediate question is whether such tests could be reliable. Blum and Noble are now analyz ing tissue samples froma large group of living subjects- Courtesy of Newsweek 284 other male partners of couples who consulted the clinic but did not have these problems. Researchers found that men who had low sperm counts were twice as likely as men in the comparison group to have used cocaine within the previous two years. And they were five times as likely to have used it once a month or more and within the previous two years, or to have used it once a month or more and for two to four years. Men with the motility problem were twice as likely as the comparison group to have used cocaine for five or