Page 89 - Ethical Guidelines for Conducting Research Studies Involving Human Subjects

Genetic Disease Diagnosis

Laboratory advances in molecular genetics have resulted in numerous clinical
applications for DNA analysis. Genetic tests can contribute a great deal of
information to clinical diagnosis. These genetic tests including PCR, fluorescence
detection, real-time PCR, and automated sequencing have been used in different
diagnostic tests. The general principles of informed consent, confidentiality and
other criteria used for any investigation in genetics should be followed. Since the
knowledge in this field is new, and relatively complicated, a DNA test must be
preceded and followed by appropriate genetic counseling.

❑ Pre-morbid diagnosis in children (clarification of each term is
required ): Parents are advised not to get the diagnosis done especially in cases
like Huntington’s disease etc. for which there is no available intervention till the
child reaches the age of proper “consent”.

❑ Pre-morbid diagnosis in adults (clarification of each term is
required): It may be carried out with informed consent. However, appropriate
genetic counseling must be provided and documented before offering such
services.

❑ DNA diagnosis in forensics: The laboratories carrying out DNA
diagnosis in forensics should follow the guidelines evolved by National
Accreditation Board for Laboratories functioning under the Department of Science
and Technology.
❑ Late-onset Neurological Conditions (untreatable) diagnostic
testing (clarification of each term is required): For example in Huntington
disease, where there are clinical symptoms, the diagnosis is confirmed according
to the number of triplet repeats in the IT15 gene increased over the usual
number. Relevant issues are consent and discussion of result disclosure to other
family members.

❑ Pre-symptomatic Testing (clarification of each term is required):
The genetic diagnosis of Huntington disease in a family member can then enable
unaffected family members to be tested to determine if they have the mutation. If
the mutation is present (a positive result) the person will develop the condition if
they live long enough. Testing can provide certainty regarding their risk and
enable life planning. However both positive and negative results can impact on
family dynamics. Again, informed consent is essential, as are the issues of ‘whom
to tell’ and ‘when to tell’.

❑ Familial Cancers (breast, ovarian, colorectal and prostate cancers
and melanoma) Diagnostic Testing (mutation searching): Where there is a
strong family history of some specific cancers, genetic testing may confirm that
the onset of cancer involves inherited susceptibility. For these conditions, the test
involves searching for the family specific mutation in the genes that have been
identified as associated with the condition. A negative result on a mutation search
only means that a genetic basis has not been confirmed. A positive result however

BMRC ETHICAL GUIDELINE ON HUMAN SUBJECTS Page 85