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17 The Healthy Person with an Abnormal Genetic Test Result: The Difference between a Presymptomatic or Asymptomatic Carrier and an Obligate Carrier

17 The Healthy Person with an Abnormal Genetic Test Result: The Difference between a Presymptomatic or Asymptomatic Carrier and an Obligate Carrier

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For example, women with a fragile X premutation have been traditionally thought of

as healthy obligate carriers, but it is now known that some of these women experience

premature ovarian insufficiency as an expression of the disease (McConkie-Rosell

et al., 2005).

Figure 3.9 demonstrates how to document genetic test results and asymptomatic

or presymptomatic and obligate carrier status. Individuals who are obligate carriers

are represented on the pedigree with a dot in the middle of the male (square) or

female (circle) symbol. Persons who are asymptomatic or presymptomatic carriers

are represented with a line down the middle of the pedigree symbol. If the person

later develops the disease, the symbol is shaded.


3.18.1 The Skeletons in the Closet

For many reasons, people tend to keep genetic information private. There is often a

sense of stigma, even embarrassment about “bad blood” or a “curse” in the family. As

Francis Galton observed, “Most men and women shrink from having their hereditary

worth recorded. There may be family diseases of which they hardly dare to speak,

and then in whispered hints or hushed phrases as if timidity of utterance could hush

thoughts. . .” (Resta, 1995). People may be reluctant to share medical and genetic

information because of fear they will be blamed for the family imperfections.

3.18.2 Choose Your Words Wisely

The difference between the right word and the almost right word is the difference

between lightening and the lightning bug.

—Mark Twain

When you take a medical-family history, you are inquiring about the very essence

of an individual. You are asking not only about the individual’s personal health but

also about intimate relationships and the health of family members (with whom he

or she may have little contact). Before you begin taking a genetic family history, it

is helpful to warn the client: “I need to ask you some personal questions about your

health and the health of people in your family. Your answers to these questions are

an important part of providing you with appropriate medical care.”

The clinician should be careful not to perpetuate feelings of guilt or fears of

stigmatization. Use words such as altered, changed, or not working properly to

describe genes, instead of mutation, bad, or faulty. Emphasize to the patient that

relatives have no choice in the genetic conditions that are passed in a family; the

diseases are nobody’s fault.

Be sensitive to terms like an uneventful pregnancy. Although a healthy pregnancy

may be uneventful to the clinician, it is very eventful to the proud parents! I often



hear clinicians refer to a family history without apparent genetic problems as a

“negative” family history, as compared to “positive.” A positive family history is

usually experienced as negative by the patient and family (Fisher, 1996). I usually

describe health problems in the family history as being contributory or remarkable as

compared to noncontributory or unremarkable in reference to the medical problems

in question.

Questioning should focus on “people-first-language” (www.disabilityisnatural.

com), with inquires about the diagnosis not the label (e.g., a person with Down

syndrome not a Down’s person, or a person with autism not an autistic). It is a

challenge in taking a family history not to focus solely on health problems, but it is

important not to use words with negative connotations such as abnormal, crippled,

retarded (intellectual disability is appropriate), birth defect (congenital disability is

preferred), or wheelchair bound (as compared to saying the person uses a wheelchair

or mobility devise). Avoid phrases that ask if relatives “suffer” or “struggle” from a


Ask questions one at a time. Do not jump from one topic to another. Begin

with general questions, and then move to more specific questions that may be more

complex or threatening (McCarthy Veach et al., 2003). Do not interrogate.

The ultimate test of the appropriateness of a question is “Will this information

be helpful to my patient” (Hill and O’Brien, 1999). If the patient asked you, “Why

do you need to know this information?” what would be your reply (McCarthyVeach

et al., 2003)?

3.18.3 Use Common Language

You are more likely to be successful in obtaining an accurate family history if you use

terms that are familiar to people. For example, rather than asking about myopathies

in the family, inquire if individuals have muscle weakness or if anyone uses a cane

or wheelchair.

3.18.4 Beware the Leading Question

If you say, “So, your brothers and sisters are healthy, right? No health problems in

your parents?” you will most likely receive a reply of “Un-huh,” regardless of whether

this is a true statement. Instead, try to be specific with your questioning by asking

open-ended questions: “Do your brothers and sisters have any health problems?”

3.18.5 Listen

Let your client tell his or her story. If the client’s dialogue is heading down a path that

is not leading to information relevant for your evaluation, gently lead the questioning

back on task. For example interject with, “That is interesting information. Now let

me ask you more about . . .”



Respect a client’s belief system of causality of a problem. Be aware of the emotional and cognitive effect that your history gathering is having on your client, and

slow your pace of questioning or pause as needed (Stanion et al., 1997).

3.18.6 Acknowledge Significant Life Events

Common courtesy should be the rule in taking a family history. If a woman tells you

that she recently miscarried or that her mother died of breast cancer a few months

ago, it is appropriate to acknowledge this with “I am sorry to hear of your loss,”

or “This must be a difficult time for you.” Conversely, the news of a recent birth,

marriage, or desired pregnancy can be greeted with “Congratulations.”

Each family history tells a story. Sometimes that story leaps from the page and

must be acknowledged. A person may be the only survivor from a house fire or a car

accident that took the lives of several relatives. A family may have perished in the

Holocaust or from a similar criminal act against humanity. Your comments such as

“That must have been hard for you,” or “I cannot imagine what that must have been

like for you,” in acknowledgment of such obviously life-changing events up-rooted

in the family tree, will be appreciated by your client and assist in cementing rapport,

respect and trust with your patient.

3.18.7 Be Sensitive to Cultural Issues and Differences

If your patient does not speak English, get an interpreter. Do not rely on a family

member to provide interpretation. The family member may be tempted to interject

his or her opinions, particularly about family matters, as part of the translation or

omit or censor information. Using an interpreter can be problematic if the interpreter

is from the same social community as the patient; in this circumstance the patient

may be reluctant to share confidential information.

Culture consists of shared patterns, knowledge, meaning, and behaviors of a social

group (Fisher, 1996). Individuals have different customs and beliefs based on their

race, socioeconomic status, gender, religious beliefs, sexual orientation, education, or

health status. When taking a family history, it is important to acknowledge belief systems that are different from one’s own. For example, a traditional Latino woman may

believe that her child’s cleft lip and palate is the result of supernatural forces during

a lunar eclipse, “susto” (Cohen et al., 1998). Individuals from a traditional Southeast

Asian culture may have strong belief in karma and fate. Several cultures believe

in the evil eye as a cause of family illness and woes (Abboud, 1998; Kalofissudis,

2003). Traditional Chinese views may relate genetics to Buddhist ideas of retribution

in this life for wrong-doings committed in a previous life. Accepted Chinese beliefs

are in patrilineal descent (through the male lines) and thus the male blood line is

genetically stronger and diseases can be passed through the male line more readily

than the female line (Barlow-Stewart et al., 2006). Persons from certain religious

and cultural groups may believe bad thoughts or sins cause a birth defect or genetic

disorder (Cohen et al., 1998). References to “bad illnesses” in the family may disturb

the “good aura” of the family or ancestors (Fisher and Lew, 1996).



An individual’s belief system is likely to influence the type of health information he

or she shares with the healthcare provider. A vivid example of this is the description of

a Hopi woman with severely disabling congenital kyphoscoliosis who was described

by her sister as being small and having pain in her legs and back that kept her from her

normal activities. The woman’s sister was not portrayed as disabled, because she had

high status in the community due to her ability to make piki, a thin wafer bread (Hauck

and Knoki-Wilson, 1996). While it is important to listen to and respect a person’s

cultural health beliefs, it is just as essential to avoid stereotypes by assuming that all

persons from that cultural share the same views of health and disease causation.

Exceptional references on providing healthcare for diverse populations are Cultural and Ethnic Diversity: A Guide for Genetics Professionals (Fisher, 1996), Developing Cross-Cultural Competence: A Guide for Working with Young Children and

Their Families, (Lynch and Hanson, 2004), Cultural Awareness in the Human Services: A Multi-Ethnic Approach (Green, 1999), and Counselling the Cultural Diverse:

Theory and Practice (Wing Sue and Sue, 2002).


Obtaining an extended medical-family history is really no different from obtaining

a person’s medical history. I usually inform the consultand, “I will now ask you

questions about you and your relatives. I am interested in your family members who

are both living and dead.” Then I ask general questions, reviewing medical systems

from head to toe. If a positive history is found, I ask directed questions based on that

system, and the genetic diseases that are associated with it. For additional directed

family history questions focused on a positive family history for several common

medical conditions (e.g., heart disease, hearing loss), see Chapter 4.

3.19.1 Medical-Family History Queries by Systems Review Head, Face, and Neck. Begin by asking, Does anyone have anything

unusual about the way he or she looks? If yes, have the historian describe the unusual

facial features. In particular inquire about unusual placement or shape of the eyes and


Anyone with an unusually large or small head?

Are there problems with vision, blindness, cataracts, or glaucoma? (If so, inquire

as to the age the problems began, the severity, and any treatment.)

Anyone with unusual eye coloring (e.g., eyes that are different colors, or whites

of the eyes that are blue)?

Do any family members have cleft lip or opening in the lip, with or without cleft


Anyone with unusual problems with his or her teeth (e.g., missing, extra, misshapen, fragile, early teeth loss)?



Any problems with hearing or speech?

Anyone with a short or webbed neck?

Anything unusual about the hair (e.g., coarse, fine, early balding, white patch)? Skeletal System.

Is any family member unusually tall or short? (If so, record the heights of the

person, the parents, and siblings. If someone is short, is he or she in proportion?)

Anyone with curvature of the spine? (If so, did this require surgery or bracing?)

Anyone with multiple fractures? (If yes, inquire as to how many fractures, how

the breaks occurred, the bones that were broken, and the age the fractures


Anyone with an unusual shape to his or her chest?

Anyone with unusually formed bones?

Anyone with unusually shaped hands or feet, such as extremely long or short

fingers or toes, missing fingers or toes? Have the historian describe these


Anyone with joint problems, such that they are unusually stiff or flexible, or

dislocate frequently? Skin.

Anyone with unusual lumps, bumps, or birthmarks? (If so, have the patient describe

them, their location, their coloration, and number.) Were these skin changes

ever biopsied or treated?

Any problems with healing, scarring, or excessive bruising?

Anyone with unusual problems with their fingernails, or toenails, such as absent

nails, or growths under the nails? Respiratory System.

Any family members with any lung diseases? (If so, were they smokers? Were

they treated for the lung condition, and how?) Cardiac System.

Anyone with heart disease? (If so, at what age, and how were they treated?)

Was anyone born with a heart defect? (If so, did they have birth anomalies or

intellectual delay?)

Anyone with heart murmurs?

Anyone with high blood pressure?

Were there any heart surgeries? (If so, what was done, and at what age?)

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