Page 69 - Ethical Guidelines for Conducting Research Studies Involving Human Subjects
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Pre-implantation genetic diagnosis (PGD or PIGD) is
genetic profiling of embryos or oocytes prior to implantation or
fertilization.PGD thus is an adjunct to assisted reproductive
technology and in vitro fertilization (IVF) to obtain oocytes or
embryos for evaluation.PGD is considered in a similar fashion to
prenatal diagnosis.
The role of prenatal diagnosis is needed or managing the remaining
weeks of the pregnancy, determining the outcome of the pregnancy,
planning for possible complications with the birth process and in
the newborn infant, deciding whether to continue the pregnancy
and finding conditions that may affect future pregnancies.
There are a variety of non-invasive and invasive techniques
available for prenatal diagnosis such as ultrasonography,
amniocentesis, chorionic villus sampling, genetic analyses of fetal
blood cells in maternal blood and biochemical analyses of maternal
serum. Methods employed for analysis of fetal and placental tissues
include pathological examination of the fetus or fetal parts and the
placenta, radiography, microbiologic culture, biochemical analysis,
karyotyping, fluorescence in situ hybridization (FISH), DNA probes
etc.
As with all medical interventions associated with human
reproduction, PGD raises strong, often conflicting opinions of social
acceptability, particularly due to its eugenic implications. For
example, in Germany the use of PGD had been prohibited by an
Embryo Protection Act, though this prohibition was partly relaxed
later. In other countries PGD is permitted in law but its operation
is controlled by the state.
PGD can potentially be used to select embryos without a genetic
defect, to have increased chances of successful pregnancy, to match
a sibling in HLA type in order to be a donor, to have less cancer
predisposition, and for sex selection.
Sex selection is indicated only in X linked disorders where male are
the sufferers. However, due to prevailing inclination for male child
in many societies, prenatal sex determination other than strong
medical indication should not be allowed.
Several genetic disorders can be detected in utero but do not have
satisfactory treatment or cures. Presently, the detection and
elimination of genetic disorders generally relies on a combination of
prenatal diagnosis plus abortion of an affected fetus. Many
individuals, regardless of their views regarding abortion, consider
prenatal diagnosis plus abortion a less than optimal solution to the
problem of genetic disease.
BMRC ETHICAL GUIDELINE ON HUMAN SUBJECTS Page 65