Genetic
counselling
The cells in our body, throughout
their lives, duplicate themselves to create new tissue.
The 23 pairs of chromosomes in a cell also double to 46.
But sometimes the pattern of duplication is disturbed.
Instead od merely duplicating a chromosome may triplicate
or even break, causing various birth defects. These
disorders can be passed to future generations.
Genetic counselling is a way to screening
high risk populations for various diseases like families
prone to cancers, thalassaemia and many genetically
transferable diseases The geneticists assess the
potential risk of passing on the disorder to future
generations. This helps the parents to be to take
informed decision about terminationg a pregnancy and
avoiding the trauma of having a disabled child.
Many couples are faced with difficult
situations regarding the possibility of a new born being
a physically disabled child or the child may be suffering
from a very troublesome illness like Thalassaemia. Some
couples have a child in their family already suffering
from thalassaemia and the prospects of having another
child with same illness is devastating. A thalassaemic
child may have to undergo repeated blood transfusions.
Some may need it fortnightly.
Genetics has come a long way to solve many
of such problems. Tests can be conducted to find out if
the unborn child carries a thalassaemia gene. Procedures
have been developed by which artificially fertilised
healthy embryo can be implanted in the uterus of an
elderly women anxious to have a healthy child. There are
also methods by which genetic maping can be done of a
person to find out if he or she is carrying any faulty
chromosome.
Some of the methods employed are --
Polymerase Chain Reaction (PCR): Is a procedure
that can reveal whether an unborn child carries a
thalassaemia gene. This procedure is done mainly to
detect minute abnormalities of the genes that cause
diseases like thalassaemia, cystic fibrosis, haemophilia
and muscular dystrophy.
Pre-implantation Genetic diagnosis
(PGD): This procedure can create and select an
artificially fertilised healthy embryo and implant it in
the uterus, and thus ensuring that the high risk couple
has a normal baby.
Karyotyping : is done to map
the genetic makeup of a person to detect any faulty sex
chromosome. Karyotyping is very helpful in showing up
chromosomal abnormalities that cause severe physical
disabilities like Tisomys - Trisomy 21 causes Down's
Syndrome, Trisomy 18 causes limb deformities and
microcephaly, Trisomy 13 gives a cleft palate.
Some
common genetic disorders
 
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