Genetic Testing

GENETIC TESTING: 1.

Consists of biochemical studies or chromosomal analysis for purposes of detecting geneticallycaused diseases.

2.

The use of diagnostic procedures for determining the presence or absence of one or more genetic traits or conditions in an individual. Tay-Sachs disease PKU - phenyl ketonuria (inborn error of metabolism)

Genetic testing usually occurs at one of three stages of life: 1. 2. 3.

neonatal period prenatally when couples are considering marriage or childbearing

CARRIER TESTING AND SCREENING: Employed when couples are considering marriage or reproduction. Helps couples to understand their relative risk of transmitting a genetic defect to their children. Examples: Tay-Sachs disease & sickle-cell anemia. Huntington’s chorea (1)

Typically both members of the couple provide cell samples which are then studied in the laboratory. If only one member of the couple carries the gene for a recessive genetic disease, then the couple is not at risk of producing a child afflicted with the disease but has a one in two chance of producing a carrier. However, if both members of a couple carry the gene for a recessive genetic disease that is not sex-linked, the couple has a 25% chance of producing an unaffected child, a 50% chance of producing a carrier, and a 25% chance of producing a child who will have the disease. ETHICAL CONSIDERATIONS IN GENETIC TESTING: Chromosomal manipulations or interventions are contrary to the personal dignity of the human being and his or her integrity and identity. ETHICAL AND PUBLIC POLICIES ISSUES: 1. 2. 3. 4.

(2)

Freedom and coercion in genetic testing and screening; Confidentiality or disclosure of test results; Access to genetic testing services; Probable benefits and harms of genetic testing and screening programs.

Freedom and Coercion: “ethics of genetic duty” – individuals and couples have a moral duty to learn what they can about the likelihood that they will transmit genetic conditions to their offspring and to take reasonable steps – steps that are compatible with their other ethical convictions – to avoid causing preventable harm to their descendants. Confidentiality and Discolsure who, besides the individual and his or her health provider, should have access to the information about the genetic condition? Two contexts: 1. Extended-family context Individuals or couples who learn that they have a genetic disease or carry a genetic trait may face decisions about whether to inform their parents, their siblings, their children, and even more distant relatives. 2. Business context Involve either employers or insurers. “the potential for misuse as well as unintended social or economic injury, information about genetic conditions should be disclosed to insurers or employers only with the explicit consent of the person tested”.

(3)

POSSIBLE BENEFITS AND HARMS: A.

Principal benefits: 1. 2. 3. 4.

B.

knowledge the ability to avoid transmitting genetic disease to offspring the ability to secure timely treatment for a genetic condition. may help to “democratize” genetic disease – it may become clearer that visible and invisible genetic problems are simply an omnipresent aspect of the human condition.

Possible harms: 1. through coercion 2. through leading to exclusion from the work force or the health care system 3. through providing incomplete information or partial services. 4. a positive genetic test may result in the stigmatization of the individual tested.