|
In order to focus on the
hereditary diseases in the Saudi society, which requires a deep
consideration due to its wide range, we asked Dr Wafa Al-Obaid, consultant
in Hereditary Diseases and Endocrine Glands, about the hereditary diseases.
Genetics has developed
greatly in the last decade in the field of knowing the genes that cause a
lot of hereditary diseases that exceed 6 thousand diseases. We can classify
the hereditary diseases to the following:
Hereditary diseases due to
different single gene carried by one of the parents or both of them .The
possibility of having a child with a hereditary disease depends on the
disease whether it can be inherited between generations. Examples of that
are:
If this disease is
inherited like a recessive character meaning both parents are holding the
same genes but it is a recessive character, then the symptoms will not
develop. However, if the baby inherits both characters from parents then he
has that disease and the baby’s vulnerability to have that disease is 25%
for each pregnancy. For instance, Sickle Cell disease, Thalassemia or
Mediterranean Anemia that spread in Eastern Province and Jizan.
The second type of
hereditary diseases is (F) type. It is transmitted as a prevailing
character meaning that it is enough for one parent to carry the gene and
the symptoms will appear on their offspring. The possibility for the baby
to inherit the disease is 50% for each pregnancy. Dwarfism is an example of
that.
Third type of hereditary
diseases is when the mother only carries the gene .She passes the gene to
the male children who became 50% vulnerable to have the disease in each
pregnancy. As for females, they carry the gene and therefore pass it to
their male children. For instance, Muscle atrophy namely “Doshin” and color
blindness.
The other type of
hereditary disease is abnormality in the number of chromosomes. This
condition occurs when the fetus is formed. Therefore, the risk of having a
sick fetus is very low. For instance, Down syndrome or Mongolism. Anyway,
there are types of Down syndrome where one parent carries abnormal
chromosomes and the chance to have another Down syndrome baby or recurrent
abortion is higher.
The most common hereditary
disease is caused by the hereditary environmental interaction. This means
that a person carries a number of genes that cause some diseases but this
requires a change in the environment conditions until that disease appears.
The most common example of this disease is diabetes. There are many genes
that cause diabetes in which a person inherits them from one of the parents
and this person becomes more vulnerable to this disease when eating a lot
or becoming less active. Meningeal Hernia and Cliff Palate disease are
examples of this type. When either one of the parents has this disease of
congenital deformities, the risk of having another child with this problem
is higher than other members in the society.
After this brief
description of the hereditary diseases, I will try to answer the frequently
asked questions by the patients’ families.
Is there any treatment for
hereditary diseases?
The answer of this question
consists of two parts: the first part is unfortunately there is no
treatment for the present time to correct the inherited deficiency of the
gene because it was formed in the first stages of fetus. Every cell in the
body carries this deficiency according to the function of the gene.
The second part of the
answer is that there is a speedy improvement in the treatment of symptoms
that are caused by the hereditary disease. For example, people with
hemolysis need blood transfer (type A) or transfer of bone marrow according
to the diagnosis. There are some diseases that require a special diet by
avoiding sugars, protein or fats and this is called the independent
diseases. Researches are still ongoing to find substitute methods to
replace the sick gene in a few numbers of the common hereditary diseases.
We often hear about the
Muscle Atrophy disease and that there is an effective treatment for it. Is
this true?
Muscle Atrophy disease is
one of the common hereditary diseases and in the last few years there were
attempts to minimize it. For instance, the use of steroids and male
hormones, which showed temporary benefits. However this disease includes
all muscles such as heart muscle, in which you can’t control the deadly end
of this disease. There are ongoing researches to replace the sick genes in
the muscle tissues.
What are the hereditary
diseases that have effective treatment and how successful it is?
Presently there is no
successful treatment for the hereditary diseases. Researches are making
attempts to treat symptoms of the hereditary diseases. There is a great
hope to find methods of treating the fetus or the abnormal gene, which is
under research. However, there are side effects such as the cyst fibrosis
of Pancreas glands.
What are the hereditary
diseases that can be treated, and how successful is that treatment?
It depends on the type of
the disease. There are
diseases that can’t be controlled through use of medications such as some
nervous system diseases, which lead to gradual deterioration in the patient
condition and can cause death.
“Diseases that are related to physical disability
specifically the hereditary diseases” can they be cured or not? And how
effective the medication is?
Unfortunately some diseases
can either be due to disorder of the function of neuroses that supply the
muscles or in muscle tissue itself. This also has no treatment and the patient
needs continues rehabilitation in order to practice his life as normal as
possible.
“Meningeal Hernia”. Is it a hereditary disease or not? What
are the causes if it is not hereditary?
The Meningeal Hernia is
either individual or with other symptoms. The reason is the failure of the
neurosentence channel to heal. Therefore it occurs in the first four weeks
of pregnancy. Moreover, there will be a failure in the healing of the
lumbar spine and membrane tissues, which results in protruded neurotissues that
lead to a disorder in the function of neuros that supply the parts of the
body under the hernia. Therefore the severeness of the disability differs
according to the place of the hernia. The hernia gets more severe whenever
the position of the hernia gets higher.
Neurosentence channel
failed to heal because the mother exposes herself to high temperature, or
because she uses “sauna rooms” in the first four weeks of pregnancy in
which she often doesn’t know about it. The other reason is the lack of
folic acid, which was known to reduce the hernia 70% in the next pregnancy.
Therefore there is a campaign in the developed countries to add this acid
to all diary products and flour.
Can medicine diagnose the
hereditary disease before it happens on the child and treat it before the
condition appears?
Yes there are ways of
diagnosing the hereditary disease in the first weeks of pregnancy and now
there is a discussion for the possibility of abortion if the fetus carries
a fatal disease in the first four weeks of pregnancy.
Diagnosing the hereditary
disease in pregnancy helps also for an early treatment for a baby after it
is born in case of metabolic diseases.
What are the new medical
discoveries in hereditary diseases?
We heard that the
hereditary map was done. This is the most prominent human development in
this century. This map specifies the location of most of the genes
responsible for different body functions. It helps researches to find out
genes responsible for many diseases that were not known before and
therefore trying to find out a way to treat these diseases.
By
Wafa Al-Obaid
Consultant, Hereditary
Diseases and Endocrine Glands
Add your comment
|
