Am I My Genes?: Confronting Fate and Family Secrets in the Age of Genetic Testing 1st Edition

CHAPTER 6

“Lightening Doesn’t Strike Twice”: Myths and Misunderstandings about Genetics

“I always thought that because I looked more like my mother, I was more at risk of getting the disease,” said Roger, who found he had the HD mutation after he had problems driving. Misunderstandings about genetics frequently arise—for example, that genes for mutations and for physical or psychological traits sort together, and that offspring tend to resemble one parent more than the other, rather than receiving equal amounts of DNA from both. In trying to grasp the meanings and effects of genetics, these individuals struggle to understand the scientific mechanisms involved, and generally have trouble doing so. They hold many misunderstandings that then affect their other decisions. Miscomprehensions emerge party because genetics is relatively new and ever-changing. Scientists, searching for continued funding, and private companies, seeking to market tests, often tout the field’s promises—and individuals yearn for information about their future.

Overall, patients, physicians, and the public have relatively little knowledge about many aspects of genetics,1,2,3,4 but the full extent and impact of these misperceptions have been little examined.

Much of the public does not know basic aspects of genetics—for example, that genes in fact reside in chromosomes in every cell in the body, 3,5,6 and that humans have 46 chromosomes.3 Most people view mutations negatively.7 Members of certain groups believe that fathers contribute more genetic material than do mothers,8 and that a child is more likely to inherit a disease mutation if he or she more physically resembles the parent with the mutation.9 Patients also misapprehend statistics—having difficulties in quantifying, and tending to overestimate, risk.10

Patients may experience and construct perceptions of risk based on both their own and their family members’ medical experiences. Overestimations of the likelihood of cancer4 may impede health, and lead to inappropriate use of prevention and surveillance.10,11 Several models have been proposed to make sense of how individuals subjectively view the nature and cause of disease and how they personalize their risk for familial disease.2 For common chronic familial illnesses such as diabetes and heart disease, individuals may assess the salience for themselves of a relative who is newly diagnosed with a disease, which can shape coping and sense of control.

Yet questions remain of how these risks and genetics are viewed by individuals who themselves are at risk for diseases for which genetic tests exist and have been marketed. It is unclear what types of misunderstandings arise related to genes and statistics, and how these may interact and affect health decisions. Questions also persist about what kinds of misunderstandings, if any, patients have about genetics after undergoing genetic counseling, and why. Though not all beliefs about a disease represent misunderstandings, some may—raising questions as to when, how, and with what implications.

MISUNDERSTANDINGS ABOUT GENETIC TESTS

Men and women here reveal a wide variety of misunderstandings about genetics, shaped by various factors, and in turn having several critical implications.

Many of these individuals see genetic assays as similar to other established medical tests—viewing genetic analyses as more definitive and predictive than these assays in fact are. “My sister thought that if she got tested, she would know whether she was going to get breast cancer,” said Karen, the lawyer with breast cancer and a family history but no testing. “Her gynecologist was encouraging her to get tested.”

Physicians may thus contribute to these beliefs in these tests’ predictiveness. Often, patients assume that a test must be worthwhile if a physician encourages it—that doctors consider a test important because it is predictive. This misunderstanding appears fairly common, especially before undergoing genetic counseling. Individuals may sense these limitations intellectually but nevertheless seek certainty, leading to conflicting perspectives or anxiety. As Karen added,

People think the test will tell you whether you will get the disease or not, rather than it being a piece of information that says, “You’re probably at higher risk for getting this disease, but it doesn’t mean you’re going to get it.” Intellectually, I understand that. But emotionally even that is hard to wrap my head around. Part of me is afraid that at some point they’ll find out that if you have the gene, you will get breast and ovarian cancer . . . part of me, this Nervous Nelly in the background, says, “Someday those numbers are going to be different.”

As a well-educated lawyer, she understands that scientific consensus can shift over time. But emotions can nonetheless outweigh intellectual subtlety. Individuals wish to reduce anxieties generated by uncertainty and want definitive answers, though such absolutes may not be obtainable.

This notion that a cause is simple and singular reflects both common lay beliefs and broader desires for certitude in a chaotic universe. Folk myths, media reports of genetic discoveries, and physicians’ implicit or explicit attitudes all frequently bolster beliefs in the predictiveness of genes, which could potentially encourage patients to pursue testing.

Many feel that the identification of a gene implies that treatment exists, or will soon be developed—that prevention and treatment is possible, as is generally the case for other clinical tests. Yet tests for genetic markers, though increasingly available, often have less clinical utility than long-established assays. Francine, the unemployed HIV-infected woman who has not had breast cancer symptoms or testing but has seen the disease in her mother, said:

I don’t know a lot about genetic testing, but if you could tell me I’m predestined to get something, at least let me know, so I can prepare myself and my kids. This way, I’ll be able to pass this information along. I’d rather know now, so I’ll know what to look forward to, and not have it sprung on me. If I know ahead of time, there are things that may be done—I can’t say to prevent it, but early treatment.

She imagines that tests reveal pre-destiny. Such beliefs arise in part because of views that genes reflect etiology and cause, not chance and unknown factors. Individuals often see science, more broadly, as able to produce treatments. Diane, who had an unexpected mastectomy but no mutation, said,

Genetic testing will probably allow people to discover much more about their DNA. Certainly, research can provide treatments somewhere down the line, maybe even alterations of the DNA. One day, maybe we’re going to beat death.

As a teacher, she maintains hope in the progress of science, despite her experience in surgery.

Many people see information for its own sake—that is, without it having a clear practical benefit—as conferring advantages. As suggested earlier, in this way, they suggest “diagnostic misconception,” akin to “therapeutic misconception,”12 in which patients assume that they will benefit from treatment provided in a research protocol even if they are participating in a randomly controlled clinical trial in which they may in fact be receiving a placebo.12

The media also fosters popular myths that behavioral genetics can uncover clear explanations for certain complex behaviors. Karl was skeptical, uncertain how much to hold HD responsible for his father’s abusiveness:

You hear a lot about predispositions for drug addiction and alcoholism, and “the gay gene”—folk information. My wife works with scientists. They know what’s going on, but are the minority.

People who have studied basic biology at an advanced high school or college level may grasp basic genetic concepts more, and view claims more warily than do others. But these myths reflect, in part, wide cultural beliefs.

MISUNDERSTANDINGS ABOUT GENETIC MECHANISMS

For most of these men and women, genetics are too abstract, entailing statistical probabilities that are far from their lived experiences. A few have vague or partial understandings of aspects of genetic mechanisms, and try to grasp basic notions of dominance and recessivity. “I don’t know,” said Wilma, who had breast cancer along with her mother, and bipolar disorder but no testing. “Is there such a thing as genes being just slightly there—you have this gene in a minute, not a more dominant way? I don’t know how that works.”

She illustrates how individuals, especially if they have not undergone counseling, can have a very poor understanding of genetics. Most have problems comprehending the basic aspects of Mendelian patterns of inheritance described earlier. With Alpha, for example, homozygous patients often don’t realize that all their offspring will be at least heterozygotes. As Dorothy, the former TV producer awaiting lung transplants, said,

Even people who have Alpha don’t understand: that their children are going to be carriers. It happens all the time on the e-lists. They say: we want our children tested. And the children turn out to be carriers. Instead, they could have had the husband tested. There’s no need to test the child, and have it in his or her record.

She highlights how misunderstandings can prompt testing that can in turn lead to unnecessary discrimination, confusion, and stress.

Beliefs about Inheriting Mutations and Physical Traits Together

Even individuals with scientific training frequently think that an individual is more likely to receive a mutation if he or she physically most closely resembles the parent with the disease. Some feel they are mutation-positive because of psychological similarities to an affected family member. As Mary, the housewife with HD, said: “Me and my mother are like two peas in a pod.”

Others grapple with these issues, drawing on their observations of their family over time, which may or may not lead to consistent conclusions. Many attempt to articulate these similarities and differences. For instance, Oliver, who continued to pursue a PhD despite having the HD mutation, feels that he looks like his father and uncle, who had the disease.

As a man, I’m obviously physically more like my father and uncle than is my sister. But there is also a certain way I move. I’ve always thought that my sister is much different. Something physically in her, the way that she carries herself, was different.

His memory may be colored by his recent genetic test, but it also comforts him, providing a sense of temporal and narrative coherence in his life. Conversely, some feel that they have escaped the mutation, since they look less like their affected parent than a sibling does. Such beliefs provide a sense of both definitiveness and closeness to a beloved affected parent.

These conceptions of jointly inheriting genes for diseases and other traits extend across all three of these disorders, and reflect in part broad cultural myths. These beliefs suggest views of behavioral genetics and physiognomy—the notion that a child takes more after one parent or whole side of the family than the other. As Gilbert, the factory worker, said about Alpha,

My oldest son is obviously his mother’s child. I’ve always thought of him as more his mother than me. My younger son is more me than my ex-wife. It’s obvious in body construction, and the problems they have—related to her lineage versus mine.

These notions that behavioral and physical traits sort together along with predispositions for disease persist strongly, and lead to assumptions about one’s own and others’ future test results, even in the face of contrary evidence and education. Sarah, the computer programmer without breast cancer or the mutation, said,

When my sister came up positive, I thought I’m probably going to be positive as well. I know it’s not logical. But I figured I probably got a good, big healthy dose of genes from that side. I remembered my high school biology, about what the percentages would be. But, it still struck me as probably a good chance.

She in fact wanted to have the mutation, because she thought it was associated with intelligence.

Folk beliefs and personal observations grounded in apparent common sense, rather than abstract intellectual understandings of genetic mechanisms, prove persuasive. As we shall see, despite counter-evidence and recognition of their illogicality, these beliefs can prevail in part due to desires for certainty in the face of ambiguity and anxiety. The persistence of these misunderstandings indicates their strength, and the challenges that clinicians thus face in addressing and correcting these errors.

Desires for certitude and explanation over randomness and chaos led some to search through history and photos of ancestors for answers regarding the source of disease. Before she found that she had the HD mutation, Linda, the art teacher, “sat down and looked through all these old family pictures—a box of old black and whites. I tried to trace the disease through us—like ‘She’s got it.’” She sought concrete visual links to other relatives, in part to feel less alone with the disease.

These men and women struggle with the possible illogicality of these beliefs. Individuals may recognize the fallacy of their assumptions but still hold them, seeking evidence of being mutation-free. Albert, the policeman who tested for HD to help his children make reproductive decisions, commented, “I look more like my father’s side of the family. I think that’s stupid, because I don’t think it really makes a difference who you look like. But I guess I’m hoping for the best.”

At times, attempts to balance acknowledgment of genetic risks with desires for hope also prompt beliefs that genetic diseases can in fact skip generations.

Getting More “Biological Material”

Individuals conceive of other genetic mechanisms in a variety of self-reinforcing ways. Sarah, as mentioned earlier, and others imagine that people receive different “doses” of genetics from each parent, as if genes were drugs. Bill, the salesman who thinks he will get HD because he resembles his father, conceptualizes “more” biological material as “cells”: “I must have the most traits, or cells, or I don’t know what from my father . . . [I] assume that if he has the disease, and I look like him, there’s a good chance I’m going to get the disease.”

Socially supported folk wisdom can fuel these beliefs that offspring receive more genetic material from one parent than the other. Outsiders may point out resemblances between a parent and a child, strengthening these notions that parents contribute unequally. As Bill continued,

As you grow up, you start hearing, “You’re just like me when I was a kid.” So you assume: if I look more like him or her, then I’m probably going to get what he or she has. In high school, hereditary means: two parents come together and pass on what they have. Whatever they have, you have. So, if you look like your dad, then most likely, if he has green eyes, I have green eyes. My dad’s got big teeth, I got big teeth. My dad had pretty big hands, I have big hands. He was a pretty fast runner, I was a pretty fast runner. Now, [I] hear my dad has that disease, and it’s hereditary, so: “I got the disease . . . I probably have more of his cells than her cells.”

As a lawyer, he is highly educated and cites high school biology, but suggests the potency of these misunderstandings. These beliefs also affect and are affected by views of complex behaviors, such as athleticism—some aspects of which may to a slight degree involve genetic differences in predispositions between individuals.

To understand the nature, meanings, and implications of genetics, many therefore search for metaphors, though these can remain elusive. Individuals struggle to grasp notions of chromosomes, drawing on analogies from architecture, computers, and weapons, though the precise details can be murky.

Controllability by Metaphysics

As mentioned earlier, many of these individuals also believe that metaphysics, and the power of the mind over the body, can control the “fatedness” of a genetic disorder—that the power of positive thinking can alter disease. Many are aware of the lack of clear scientific grounding for such beliefs, but adopt them nonetheless.

These men and women also invoke metaphysics by expressing altruistic wishes that a family member would not have a mutation. Joyce, the spa employee who blamed her breast cancer on urban stresses and had a strong family history but no mutation, felt that “my siblings are never going to get it—because they’re my siblings, and I don’t want them to.”

Similarly, notions emerge that a parent would simply not give his or her children a mutation—as if it were a conscious choice—or that an individual has the power to eliminate a mutation from the family. Individuals thus assign agency and volition to genes. Linda, the art teacher who felt overwhelmed by the “HD nightmare,” felt that her father was here on earth to get rid of the disease in the family. She lacks the mutation, and believes that her father willfully, stoically, and heroically “took it on” to eliminate it. Beliefs about parental responsibility for transmitting a mutation or not can thus reflect misunderstandings of genetics.

I had this real strong feeling that my dad had come to clean it up—to finish off this nasty, ugly business, and that my sister and I were going to be fine. He took this thing on, and was going to wrestle it down for us. I also thought that if anybody has it, it would probably be her. Three days after my dad’s funeral, she was going to get her results. She sat in front of me in the car, and I put my hands on her, and thought, “Take it away. Make me have it, so you don’t have to.” My dad was the best support I ever had. I just really thought that he wouldn’t have given me such a thing.

Even after genetic testing and genetic counseling, individuals may maintain these misunderstandings. As we have seen regarding causality, people may actively pursue ways of supporting such prior views.

MISUNDERSTANDINGS OF STATISTICS

Misunderstandings arise about not only genetics, but statistics as well. For instance, people do not always grasp differences between percentages and proportions. As an engineer, Benjamin said about Alpha,

A lot of people don’t understand arithmetic odds. I’ll say, “There’s a 3% chance that your mate is going to be a carrier.” They’ll say, “Well, talk to me in real numbers.” So, I say: “There’s a one in 35 chance.” I try to explain it in simple terms. They don’t understand percent. I’ve always worked with numbers. I’m kind of anal.

His professional experience and psychological and cognitive predisposition help, and distinguish him here.

Misunderstandings emerge as well concerning interpretations of absolute versus relative risks. A genetic test may triple a patient’s risk from 1 in 1,000 to 3 in 1,000, though the odds of occurrence in fact remain relatively rare. Individuals may accept only one of these sets of statistics, rather than both. Beatrice, the Latina math teacher with breast cancer but no mutation, recognized how other patients may frequently confuse these two sets of figures:

Somebody said that if I took tamoxifen, I was going to double my chances of uterine cancer. That was scary. But then I said, “Well what are my chances if I don’t take it?” They said, “1 in 10,000.” I said, “That means it could be 2 in 10,000?” I said fine, just give it to me. People throw numbers out, and if you don’t understand or question it, it could be scary.

Thus, individuals need to look at both absolute and relative risks. Yet even clinicians may fail to do so, and use statistics incompletely and sub-optimally. Due to her advanced quantitative education, Beatrice knew to ask about absolute risks, which were still small. Yet many patients may understand these numbers only partially, if at all.

Beatrice wonders how less educated patients handle all this information. With graduate school training, she feels she was able to make an informed decision, but she is concerned for others. She continued,

In the waiting room, there is a wide range of socioeconomic levels. How do some of these people deal with this information? How is it presented to them? A lot of information comes at you fast and furious, and you’re trying to decide what applies to you.

Each Toss of the Coin as Independent

Misunderstandings of genetics and statistics often occur together. Even many well-educated people feel that the probabilities of susceptibility among siblings are not independent, but linked. Hence, some think that if two siblings are at risk for HD and one is found to have the mutation, then the other will therefore not have it.

Many at risk of HD, in particular, find the alternative—the fact that each toss of a coin is independent—to be counterintuitive, in part because of countervailing emotional desires and beliefs in cosmic fairness. Several individuals feel that an inherent logic of cosmic fate operates here (the notion that “you can’t escape twice”). John, who had dropped out of graduate school when learning about HD in his family, said that before he learned he lacked the mutation he became frightened when his brother tested mutation-negative.

Irrationally, I thought for sure that we couldn’t both get away unscathed. I know they’re independent events, so the fact that he tested negative does not influence my testing at all. But emotionally, it didn’t feel that way at all.

John held this belief for a period of time, despite recognizing its illogicality.

These misunderstandings can affect coping, and responses to both one’s own test results and those of others. John added that when he learned that his brother lacked the mutation,

I was devastated. I couldn’t talk to him. I got off the phone, and cried, thinking, “I’ve got it for sure.” I knew it was irrational. I told him a few days later, “Look, I just can’t celebrate this with you. I’m sorry. It is good news. But I’m having this irrational response, you’re just going to have to enjoy this without me.”

John eventually learned that he, too, was mutation-free.

Genetic counseling can help alter these beliefs, but many individuals may get tested through either physicians or direct-to-consumer marketing companies that provide little, if any, counseling. Hence, these misunderstandings can drive testing and other decisions, without counseling. Individuals may realize only later that they misunderstood, and may then feel overwhelmed. As John continued,

One woman in my support group had a sister, and convinced herself that this sister had the gene—because she was so much like their father in personality. Then this sister got tested, and didn’t have it—so this woman flips out. She had never worried about HD. She was 45, had this 8-year-old kid, and suddenly thought, “Holy shit, I got it all wrong!” She was a wreck, very agitated. I was worried.

Benjamin, the engineer, observes this misunderstanding among patients and family members with Alpha, too, and often has to correct it, telling them, “It’s the same odds every time you flip the coin.”

These beliefs appear widespread, tapping into ostensibly common sense notions of statistics and risks. At times, even patient support groups and advocacy organizations implicitly disseminate these notions. Before learning she lacked the mutation, Linda, who felt overwhelmed by the “HD nightmare,” said,

When my sister didn’t have it, it was like, “Oh geez, it couldn’t really be that we would both escape.” I gather it’s not that unusual. But when you tell that to a support group, they all go, “Mm-mmm . . .” because the likelihood is not high, if you have two or three siblings in a family, that they all escaped.

Misunderstandings of statistics and genetics can in fact reinforce each other. Individuals may be aware of classic Mendelian principles, but misinterpret them. Roberta, the former nursing student who had breast cancer, as did her mother, but has not been tested, explicitly cited Mendel’s law. But she misconstrued it, in explaining why her relatives, who are both sickle-cell carriers, attempted to have a child without the mutation. “We went back to old Mendel’s law about four,” she said. “They said you have two kids already, so you need to hit it this time, or we’ll miss it altogether. So they tried it once more.”

The Existence of Two Options Means the Odds Are Fifty-Fifty

As we have seen, some assume that the existence of two outcomes—having or not having a mutation—means that the odds of either outcome must be fifty-fifty, regardless of epidemiological data to the contrary. These individuals thought that the number of options predicted the odds, again reflecting misunderstandings of both statistics and the predictiveness of a particular test. Laura, the graphic designer and former environmentalist with a strong family history of breast cancer but no symptoms, said, “If you test negative, you have the same risk as the general population, so there was a 50% chance that I really didn’t need to be going through all this, because I might be negative.”

She appears here to confuse several phenomena. Odds of 50% apply for HD, but not for other tests such as BRCA. In fact, she has a higher risk than the general population because she has a family history. If she did have the same risk as the general population, the chance of her being mutation-negative would then be over 98%—not 50%. The risk of breast cancer in the general population is approximately 12%,13 and the prevalence of BRCA1/2mutations is approximately 0.24% among non-Ashkenazi Caucasians, and 1.2% among Ashkenazi Caucasians.14 Though Laura has already undergone genetic counseling, she nonetheless maintains these misunderstandings. Importantly, her miscomprehension led her to think she could have avoided testing. She suggests here, too, how miscomprehension of epidemiology can prompt misperception of one’s own risk.

FACTORS INVOLVED

Several factors may shape the types and likelihood of individuals’ misunderstandings. As suggested, education both generally and specifically in science can potentially reduce these errors. Miscomprehension can prevail, fostered by irrational beliefs (such as that desires to avoid disease can by themselves prevent illness). Individuals may realize intellectually that their beliefs are illogical, but nonetheless hold to them.

Emotional factors such as minimization, denial, and hope can bolster these misperceptions. Several of these men and women mentioned “denial,” which suggests a psychodynamic defense mechanism, but has entered general parlance more widely and can perpetuate misperceptions about genetics and risks. Joyce, as mentioned earlier, “was in incredible denial.” She did not think that the fact that her grandmother and aunt had breast cancer would increase her own chances of disease. People may have little desire to counter such minimization of their risk. Yet such denial, if challenged by external events, can crumble, leaving a person devastated. As Joyce said, when the diagnosis hit her it was “like a ton of bricks.”

Several people believe that they received a mutation or a disease as punishment that they deserved. Questions arise about the accuracy of such metaphysical notions. As Karen, the lesbian lawyer with breast cancer but no testing, said,

I felt I must have really fucked up. Did I fuck up because I had done immoral things? I was living an immoral life, not eating well, not exercising, not paying attention to my body. Am I being punished? I also had an affair while I was with my partner. If I hadn’t had an affair, or if I lived a more morally upstanding life, I wouldn’t have gotten cancer. My rabbi said, “I don’t think about God as punishing in that kind of way.” I’m 95% over that.

Though a well-educated professional with a family history of the disease, she has still not entirely moved past these beliefs. Some may argue that these beliefs, though unscientific, are not necessarily misunderstandings per se, and may merely reflect religious views. Nonetheless, these concepts may inadvertently impede health behaviors, and awareness of them is therefore important.

Various social contexts may abet or challenge these misunderstandings. Support groups, the media, and hearsay can all promulgate myths. A patient may feel that in certain social contexts other people may view such beliefs as irrational. But he or she may nonetheless maintain these views. Linda, the art teacher who thought that her father would eliminate the disease from the family, said about the period before she tested mutation-negative:

I was very much a part of the New Age claptrap. A friend sent me a guru healing tape—this guru believed that some people came into the world to extinguish a genetic disease in the family. Now, it’s a little embarrassing to me. I’m from California, so you can take this with a grain of California salt.

As she suggests, friends and family members may fuel beliefs that an individual may accept or reject. But disagreements about these understandings can produce strife. Carol, who had breast cancer in her family and had her breasts and ovaries removed due to the mutation, said,

My boyfriend is Mr. Holistic Vitamin Guru, crazy nut. He thought my breast cancer could just be treated with vitamins. He is dead against everything I’ve done, downright mad that all this has gone on, which has been difficult. He doesn’t really understand that in every single gene in my body, this one gene is mutated. He just thought this one mutation is on one something, but not on every chromosome. I had to have the doctor tell him: this is in every single gene in my body . . . It cannot be fixed. He just thought it was just a small corruption of some sort that can be corrected in one place in my body, like my breast. So, he didn’t understand why all this stuff had to happen, having my breasts and ovaries removed.

She confuses the meanings of “gene,” “cell,” and “chromosome,” but underscores tensions that can exist about misunderstandings of mutations and their treatability.

An individual’s disease can also distress a spouse who struggles with his or her own anxieties about the diagnosis, and miscomprehensions or desires not to understand. The fact that disease can result from a mutation can be both frightening and counterintuitive. Carol added about this boyfriend:

I don’t think he wants to understand. My breasts and ovaries had to be removed, but those genes are still lingering there . . . I could still get cancer. It could metastasize to another part of my body.

These misperceptions can impede health behaviors and coping, leading to avoidance of testing or treatment. Joyce, with a family history of breast cancer, said that before she got the disease and found she lacked the mutation:

I thought: if I didn’t have a mammogram, I wouldn’t have breast cancer. So I’ve never had a mammogram. I always thought breast cancer was overtreated—that the whole thing was a crock. Why not get a mammogram? Foolish risk-taking—it was exciting. I also did exercise and diet. That strategy did not work.

She suggests magical thinking here—if not tested, she wouldn’t develop the disease—and wariness of shifting medical science, and concluded that behavior, rather than biology, controlled her disease.

CONCLUSIONS

A variety of misunderstandings about genetic mechanisms, tests, and statistics emerge here. These tests are frequently seen as being more predictive than they actually are, and genetics are viewed as able to predict even behaviors and traits for which no markers have yet been identified. Misunderstandings arise about genetic mechanisms, carrier states, homozygosity versus heterogeneity, and the amounts of biological material one inherits from each parent. Misconceptions about statistics concern percentages versus proportions, absolute versus relative risks, and independence of odds. As we will see, these miscomprehensions shape testing, treatment, coping, and reproductive decisions.

Expanding use and direct marketing of genetic tests to both patients and providers make these issues critical. Private companies, scientists, journalists, and physicians may overly encourage genetic testing, taking advantage of and contributing to beliefs in the intrinsic value of this knowledge. Genetic testing often then becomes imbued with undeserved magical power—as potent and portent.

While earlier studies have noted that the general public misunderstands genetics, and that individuals at risk of common chronic familial diseases for which no definitive genetic markers have been identified (e.g., hypercholesteraolemia and diabetes) view these disorders in highly subjective, personal ways,15 the men and women here confront disorders for which definitive tests exist. Frequently, they have already interacted with genetic counselors and other providers regarding these issues, but nonetheless still display numerous misconceptions.

While prior researchers have proposed possible frameworks for genetic counseling that include perceptions of risk,16,17 the men and women here suggest how such perceptions of risk may be based on misunderstandings. Multiple factors such as views of cause, control, and family influence have been suggested, and may affect perceived risk. But the interviewees here reveal how some of these variables can in fact interact and vary, based on emotional and psychological needs that can collide with or override intellectual understandings of genetics. Broader cultural and social myths and misunderstandings can clearly affect these perceptions as well.

Several of these issues have received little if any attention among providers and researchers. For example, the notion that disease mutations are linked with physical resemblances to an affected parent has been suggested among individuals at risk for HD,9 but arises here with other diseases as well. These men and women also elucidate other aspects of this phenomenon—how it persists despite awareness that it may be illogical, and how it supports and is supported by other misunderstandings and reflects desires for order in the face of anxiety and despair.

Misunderstandings about statistics and genetics fuel each other. Prior research has tended to separate misperceptions of statistics, genetic tests, and genetic mechanisms. But these three sets of misconceptions can in fact reinforce each other. The notion that genetic tests are more predictive than they actually are can both result from and contribute to misconceptions about statistics. Patients overestimate not only their risk, but the predictiveness of genetic tests. These overcalculations can bolster and be bolstered by beliefs about genetic mechanisms. Difficulties grasping complicated statistics (e.g., concerning relative proportions, and independence of odds) can exacerbate misunderstandings about genetics. Misperceptions of statistics and genetics may both also reflect emotional states and desires (related to hope, denial, and control). These emotions can outweigh educated understandings of how genetics and statistics actually work.

Personal experiences, education, inherent scientific uncertainties, emotional issues, and social inputs can all contribute to these miscomprehensions. When test results challenge prior assumptions (e.g., that physical resemblance among family members predicts the presence or absence of a disease mutation), some individuals conclude that these assumptions were incorrect. But others strive to maintain these beliefs, and reconcile these divergences.

At times, a sense of therapeutic misconception about testing appeared—that tests must be helpful in and of themselves in providing answers. Individuals frequently overestimate the power of genetics—for example, believing in genetic bases for behavioral traits for which no genetic markers have been found. Many think that testing is inherently beneficial in and of itself—that knowledge is invariably power—and that physicians would not offer medical tests if these were not beneficial. On the other hand, especially for HD, with its particular stigma, patients who are relatively well-educated about genetic risks (frequently due to family experiences) may value testing less for its own sake, since they are more aware of the potential discrimination that can result.

Patients seek perceived personal control,18 and many come to believe that they can in some way affect genetic disorders (even HD). Yet these beliefs may in fact be incorrect, impeding coping. Hope, denial, and despair can shape and be shaped by these misconceptions.

Kahneman and Tversky19,20 described difficulties in grappling with statistics, and the heuristics people then use, and suggest that humans are generally risk averse. The individuals here try to view and frame genetic information positively, seeking hope. They also respond to these challenges by seeking to reduce uncertainty, seeing genetic tests as more predictive than these in fact are.

Notions that genes are highly predictive and that metaphysics can alter health reflect widespread cultural views—disseminated in part by the media—and can enhance personal beliefs. This social reinforcement underscores needs for improving public education about genetics. At the same time, providers need to recognize that patients’ misperceptions may partly stem from such widespread social attitudes, which thus need to be addressed. A patient may recognize the inaccuracy of socially disseminated notions about genetics, and reject or be swayed by these. Alternatively, patients may hold inaccurate beliefs that providers or the media can correct. Nonetheless, as we have seen, given the ambiguities of genetic information and competing emotional needs, inaccurate perceptions can persist.

Prior research has suggested that individuals who were at risk for HD, whether symptomatic or asymptomatic, generally had lower levels of distress than expected.21 The men and women here elucidate how patients in fact manage to incorporate positive test results and symptomatology into their lives through social, cognitive, and other psychological processes. Yet these processes may at times involve miscomprehensions that can impede health behaviors.

These data illustrate how individuals conceptualize genetics within the contexts of their other beliefs. At times they have almost mystical senses of fate—of “things meant to be”—as opposed to diseases occurring through biological processes. Individuals ponder genetics not in isolation, but as part of larger cosmological beliefs and understandings, seeking order and fairness.

Earlier researchers have also suggested that patients personalize their views of genetics, yet the men and women here highlight the importance of examining not just how views of risk are subjective, but of what specific elements these beliefs actually consist (i.e., the specific content) as well, and how these perceptions may in fact be erroneous. Moreover, these misunderstandings are not always wholly idiosyncratic, but reveal patterns related to cultural myths and reflect underlying desires. Clearly, not all subjective impressions of genetics are inaccurate, but some are, and patients may benefit from clinicians, patients, family members, and others recognizing and trying to correct these.

With these three diseases, some possible differences emerge. Specifically, the genetics for HD is less ambiguous than for these other two disorders. BRCA mutations involve more uncertainties, given the reduced penetrance of the mutations and the potential effects of other, nongenetic factors in disease onset and severity. Similarly, for Alpha, confusion can result since environmental exacerbants can worsen symptoms, and heterozygotes can themselves get sick, though less severely than homozygotes. Thus, misunderstandings of absolute versus relative risks arise for breast cancer and Alpha, but not for HD. Nevertheless, many similar patterns clearly emerge across these disorders.

Correct perceptions in one domain can potentially help counterbalance misperceptions in others. While genetic counselors are trained to probe and address misunderstandings, physicians, nurses, and family members may be less aware of the breadth and prevalence of these misconceptions and the ways these may shape patients’ health decisions. Yet these areas need to be addressed carefully, given the sensitive emotional issues of denial and hope. With rising amounts and murkiness of genetic testing, heightened appreciation of these issues is vital.