FOR MICKEY MANTLE, JR., CARRYING AROUND THE GENETIC load of one of the century’s most famous pro athletes has been a mixed blessing. It has given the 45-year-old Dallasite the guileless good looks and aw-shucks nonchalance that made his father one of our most beloved celebrities. And as he himself admits, “People will return your call, no matter what you’re calling about.”

But genetic inheritance cuts both ways, and in Mickey Junior’s case, it has also left him vulnerable to two vexing diseases: alcoholism and cancer. In fact, when Mickey Senior passed away, on August 13, 1995, it was difficult to know which of the two finally did him in, since he died of cancer of the liver, an affliction that can be genetically predisposed but is also precipitated by chronic alcohol abuse. (Mickey Senior also carried the hepatitis C virus, which is a leading cause of liver cancer.)

Mickey Junior dealt with his own alcoholism (and drug abuse too) not long after his father’s death by seeking help for his addictions, just as his parents and brothers had. But the cancer was not so easily dispensed with. Cancer makes you wait on it, and even if you’ve waited all your life, it can sneak up on you. Mickey Junior first noticed the lesion on his neck last June. “Frankly, I didn’t worry too much about it at first,” he recalls. “It looked like a minor skin cancer, but I’d had lots of those—maybe twenty or twenty-five small lesions over the past eight years. They had all been little things that my dermatologist had excised, and that was that. But this one turned out to be different.”

For the Mantles, the news that Mickey Junior had cancer was a frightening instance of déjà vu, the unwelcome return of a disease that has killed too many men in the family. In addition to his father, Mickey Junior’s grandfather and two of his uncles all died at relatively young ages of Hodgkin’s disease, a lymphatic cancer, and his younger brother Billy battled Hodgkin’s on and off before dying of a heart attack at age 36. “No question about it,” says Mickey Junior. “You have as many people die of cancer as we have and you always will think the worst.”

Anyone who heard or read of Mantle’s brush with the Big C had to ask the same awful question: If cancer begins to turn up in my family, does that mean I’m doomed? Until recently, there wasn’t a clear answer—and in some respects, there still isn’t. In the past few years the disciplines of oncology and genetics have made breathtaking inroads into the previously impenetrable mysteries of the disease: Scientists have figured out what sort of damage to which genes may foment a malignancy, marked numerous genes as the primary carriers of the major cancers from one generation to the next, and identified which “syndromes” of cancer in families are most likely to afflict future generations. But as always seems to be the case with each new cancer discovery, the additional insight has given rise to new questions, ambiguities, and outright misconceptions. More than most other diseases, cancer has the ability not only to maim and kill but to terrorize. As a consequence, fear of cancer in the abstract has always been a kind of pathology unto itself, the chief symptom of which is the hysterical exaggeration of a modest body of firm fact into myth.

The explosion of knowledge about heredity and cancer has been no exception. The confirmation that some cancers are hereditary has led people to believe that all of it must be, at least to some extent. Some hyperneurotic souls conclude that even a handful of isolated instances of cancer in their family tree represents a hereditary pattern and that they are therefore condemned. Others fear an invasion of privacy in an age in which one’s predisposition to cancer can be predicted: If a genetic screening for, say, breast cancer turns up positive, won’t that finding provide the basis for job and health insurance discrimination—even if the disease never materializes?

None of these worries is any more valid than our worry a few decades ago that cancer was contagious and could be caught like the flu. Indeed, one of the more interesting things that the brief history of clinical cancer genetics has taught us is how relatively infrequent true hereditary cancer is. And further, how even in a seemingly obvious case like that of Mickey Mantle, Jr., things aren’t always what they seem.

WHEN MICKEY JUNIOR’S CANCER WAS DIAGNOSED IN MID-1998, he’d finally settled into a comfortable routine. He’d been clean and sober for three years. Though he’d been divorced for six years, his relationship with his nine-year-old daughter, Mallory, had never been better. His work life—split between working with the Mickey Mantle Foundation and helping run the family businesses that licensed the use of his father’s name—was busy and productive. But things hadn’t always been so orderly for the namesake of the baseball hall-of-famer. Mickey Senior had observed not long before his death that if he’d known he was going to live so long, he would have taken better care of himself. While Mickey Junior had never lived his life with quite the same reckless abandon, he’d had trouble figuring out what he wanted to do.

Perhaps that was because of a childhood necessarily spent on the move. Mickey Junior was born on April 12, 1953. (“Just in time for opening day,” his mother, Merlyn Mantle, wrote in A Hero All His Life, a 1996 tribute to her husband. “In June, I flew with him to New York so he could finally meet his daddy.”) As a kid, he was shuttled between the Mantles’ home in Commerce, Oklahoma (and later, their adopted hometown of Dallas); New Jersey, where they lived during the summer while Mickey Senior played at Yankee Stadium; and St. Petersburg and Fort Lauderdale, Florida, the Yankees’ spring training sites. Young Mickey had at least some of Mickey Senior’s natural athleticism: At age seven he took up golf and, encouraged by his dad, became proficient in his teens. He also showed a talent for baseball, eventually playing two years in the minor leagues. Unfortunately, at the same time, he was following another genetic bent by drinking and using drugs.

He never graduated from Hillcrest High School, though he earned an equivalency degree. He went to junior college in Dallas for a while, worked for an oil company, sold life insurance, and got a real estate license. He wasn’t consciously running from the prospect of a fatal disease, but as time went on, he was more and more aware of it. In 1977 his brother Billy, then nineteen, was diagnosed with Hodgkin’s. Billy’s bouts with surgery, chemotherapy, and radiation, not to mention his own alcohol and drug use, were hard enough for Mickey Junior to take, but even worse was the knowledge that Hodgkin’s had shown up in his generation. “It concerned me and my brothers,” he says matter-of-factly. “It sure did.”

Still, when the lesion turned up on the left side of his neck last summer, Mickey Junior brushed it off. That led his brother David to worry that he was acting a little too much like their father always had. “He’d been having these things off and on, and he looked to me like he’d lost weight,” David says. “You just can’t ignore that in our family.”

In June Mickey Junior finally went to his dermatologist, who performed a biopsy on the superficial lesion. It was a squamous cell skin cancer, which, along with basal cell carcinoma, accounts for the vast majority of non-melanoma skin cancer. During a subsequent examination, though, the dermatologist noticed a lump beneath the skin in the same area as the lesion, and referred Mickey Junior to surgical oncologist Robert Steckler at Medical City in North Dallas. After analyzing the mass, Steckler told him he had a “very aggressive” form of squamous cell skin cancer that had invaded at least one lymph node. “He called it a man-eater,” Mickey Junior says. “All I could think of was how my brother Billy had found a lump in the same area before they said he had Hodgkin’s. Now I was legitimately worried.”

HE SHOULD HAVE BEEN—THOUGH IN truth, the odds are just as good that Mickey Junior’s tumor was a so-called sporadic cancer, the result of lifestyle and environment.

All cancer is genetic in that it involves damage to and dysfunction of certain genes responsible for regulating cellular replication. But these damaged genes are truly inherited—that is, passed from parent to child at conception—in only 5 to 10 percent of the most prevalent cancers: breast, ovary, colon, prostate, and melanoma. The remaining 90 to 95 percent is due to genetic damage incurred after birth: simple wear and tear on the body over time, poor diet, and smoking and other long-term exposures to cancer-instigating substances.

“We forget that cancer is very prevalent,” says Dr. Gail Tomlinson, an assistant professor of pediatrics at the University of Texas Southwestern Medical Center at Dallas and an expert in cancer genetics. “If you remember that one in three of us will develop some form of cancer during our lives, then you realize that a person could have a lot of instances of cancer in his extended family and none of it would necessarily be hereditary.” Indeed, while cancer can tend to “cluster” in certain families, Tomlinson notes that the answer isn’t always pure heredity. A multigenerational chain of it, could just as easily be the result of shared geography or diet (a lifestyle factor said to be responsible for 35 percent of all cancers). In the Mantles’ case, many of the men afflicted with Hodgkin’s disease spent most of their life in the lead and zinc mines that were once the primary industry in northeastern Oklahoma—and such exposures have been known to instigate various cancers.

Then there is the issue of “syndromes.” A syndrome is a clearly hereditary run of cancer in a family and may involve malignancies at different anatomical sites—breast, ovaries, prostate—as well as non-tumorous symptoms through several generations, all results of similar genetic damage. When such cancers follow a clear pattern of genetic inheritance—dominant or recessive—they’re called hereditary; those that do not follow an identifiable pattern of inheritance but appear in multiple family members are called familial clusters. Outside of the well-defined syndromes, it is not conclusively known whether a long line of, say, Hodgkin’s disease can be responsible for a later incidence of, say, squamous cell skin cancer. In Mantle’s case, this suggests that while he’s probably always had a predisposition to Hodgkin’s, he may be out of the woods, since the tendency in his family has been for early onset. As for the skin cancer, Steckler states flatly, “Mickey got it because he’s fair-skinned and fair-haired. That’s the prototype for acquiring skin cancer.”

And even a diagnosed genetic predisposition still doesn’t come close to being a death sentence, says Dr. Gordon Mills, the chairman of the Department of Molecular Oncology at the University of Texas M. D. Anderson Cancer Center in Houston. For one thing, heredity only predisposes the individual to affliction. It still takes seven to nine genetic mutations to form a cancer, Mills explains, and the inherited gene is but one of them. “And the changes have to take place in the same cell,” he adds. “All it really means is that you have a head start on development of the disease.” Mills cites the newest figures on breast cancer as proof that even when members of a family are prone to cancer, it is far from certain that a descendant will actually develop it, let alone die of it: Among women with strong histories of breast cancer in their families, only 30 percent tested positive for one of the two main breast cancer genes—and of those, only 50 to 60 percent will actually develop the disease during their lifetime.

Not that heredity means nothing. Both Mills and Tomlinson are quick to point out that someone like Mickey Mantle, Jr., has every reason to be more sensitive to cancer’s warning signs than does someone with absolutely no cancer in his family history. With the more common and well-researched malignancies like breast cancer, there are established odds for developing the disease based on its history in your family: For example, if your mother had breast cancer at any age, your relative risk is 1.7 times to 4 times that of a person with no family history; with more first-degree relatives involved—say, a mother and a sister—and premenopausal onset, your relative risk runs many times that of the control group. And as genetic science uncovers and marks more genes related to specific cancers, the percentage of heredity cancers may rise. One recent study has even suggested that the most “lifestyle-acquired” cancer, lung cancer, may have a slight hereditary component: The offspring of smokers who died of the disease seemed more prone to it, even if they themselves didn’t smoke.

But in general, Tomlinson says, the fear of inherited cancer tends to be out of proportion with the actual threat. A person should be concerned if he can establish the following about his family’s history with the disease: Two or more confirmed cancers of the same kind in two or more first-degree relatives; early age of onset, generally meaning at least ten years earlier than is normal for the disease (with breast and colon cancers, the average age of onset is between 50 and 60; with lung cancer, it is 65 or so); and the presence of rare cancers at an early age in the family history.

If some or all of those factors are present, you may be a candidate for genetic-risk counseling and DNA testing. Counseling involves working up a family pedigree detailing your ancestors’ experience with cancer and your odds of inheritance. Testing, which is generally available for major hereditary cancers like those of the breast, ovaries, prostate, and colon, can locate a cancer gene if it has been passed on. Such counseling and testing are useful for (1) getting a better fix on your cancer risk, (2) determining the seriousness of a tumor if you already have cancer, and (3) determining the reproductive risks if you’ve undergone radiation or chemotherapy. Mills and Tomlinson both stress that counseling and testing are not for the mildy curious: The processes can be expensive—several hundred dollars for the former, several thousand for the latter—and are designed primarily to help members of families who have a documented cancer history. If your risk of cancer is nothing out of the ordinary, Mills says, you should simply observe the standard risk-reducing behaviors: don’t smoke, drink in moderation, and watch your diet. Beyond that, it’s all left to chance. “One other thing that heredity-cancer findings have confirmed for us,” he says, “is that a lot of cancer is still just plain bad luck.”

MICKEY MANTLE, JR., HAD NEITHER the time nor the inclination to ponder such matters before Steckler had him on the operating table. In August the oncologist performed a radical neck dissection, an operation in which the lymph nodes on one side of the neck are removed along with the nerve that serves the trapezius muscle. “This was a case where you had prior skin cancers,” Steckler says, “and you had this one going all the way to one lymph node. You didn’t want to take any chances.” Because of that, Mickey Junior underwent a lengthy round of forty radiation treatments to make certain every last bit of the squamous cell carcinoma was terminated.

Five months later the area on his neck behind and below his left ear is still noticeably distended with thick scar tissue. His neck and face are a deep, almost purplish red. But his checkups, he says, have been “so far, so good.” The only real damage has been to his golf swing, a consequence of his stiffer-than-normal posture—and that will improve.

Mickey Junior’s brush with cancer has left him chastened about how much time he spends unprotected in the sun, but he’s unwilling to let it run his life. “I think it’s a waste of time worrying,” he says, again sounding more than a bit like his father. “You should take care, but I really think you can make things worse by sitting around thinking about it.”