1. Genetic disorders are caused by changes or mutations in genes or chromosomes. Methods to prevent genetic disorders include genetic screening and testing, genetic counseling, vaccinations, and supplementation. 2. Genetic screening programs like prenatal screening, carrier screening, neonatal screening, and premarital screening help identify risks for genetic conditions. Techniques include blood tests, ultrasounds, and in some cases tissue sampling. 3. Factors that can influence fetal development and potentially cause birth defects include certain medications, illnesses, nutritional deficiencies, and environmental exposures called teratogens. Maintaining good prenatal health through diet, exercise, avoiding teratogens, and taking folic acid can help reduce risks.

1. Prevention of genetic
disorder
Done by:
Wafa Bahshwan
Hind alshankiti
Hanan bamousa
Hayah selali
Under the supervision:
Dr.Mohammad Al-hefny
4/4/20181

2. Prevention of genetic disorder
• What is genetic disease ?
• Methods to prevent genetic disorder .
• Screening program in KSA and worldwide ( PMS ,NNS ) .
• PGD
• Teratology and teratogens ( definition , effect ,example )
• Maternal health during pregnancy .
4/4/20182

3. 1- What is genetic disease ?
A genetic disease or disorder is the result of
changes, or mutations, in genes or chromosome .
(Abnormalities can be as small as a single-base mutation in just one
gene, or they can involve the addition or subtraction of entire
chromosomes).
4/4/20183

4. 2- Methods to prevent genetic disorder
Genetic screening
and testing genetic counseling
Vaccinating and
supplementation
4/4/20184

5. 2.1 - genetic counseling
Genetic counseling is a process to
evaluate and understand a family's
risk of an inherited medical
condition.
A genetic counselor is a
healthcare professional with
specialized training in
medical genetics and counseling.
4/4/20185

6. 2.2- Genetic
screening
and testing
PMS
Prenatal
screening
Carrier
screening
NNS
PGD
4/4/20186

7. 2.2.1- Carrier screening
4/4/20187
offered to individual who
have a family history of a
genetic disorder & people
in a ethnic group with an
increased risk of specific
genetic conditions
if both parents are tested
, the test can provide
information about a
couples risk of having a
child with a genetic
condition.

8. 4/4/20188

9. 2.2.2-Prenatal screening
Prenatal screening is offered during pregnancy to help identify fetuses that have
certain diseases ex; (Down syndrome)
These usually involve blood tests , an ultrasound and some times Chorionic Villus
Sampling
4/4/20189
They test baby overall
development and check
to see if
baby is at risk for
genetic conditions.
They also check baby
for heart defects,
cystic fibrosis, and
other developmental
problems

10. ِEX of Diseases diagnosed by Prenatal screening
4/4/201810

11. Diagnosis used in prenatal
screening
4/4/201811

12. 2.2.3- NNS in Saudi Arabia
There is more than 30
board certified clinical
geneticists in Saudi
Arabia.
4/4/201812
The first Saudi national
newborn screening
program was for congenital
hypothyroidism and was
established in November
1989
More recently, the MOH
has assumed full
responsibility of newborn
screening, which is now
performed as a national
program.

13. 2.2.3- Neonatal screening (NNS)
Neonatal screening is the practice of testing every newborn for certain
harmful or potentially fatal disorders that aren't otherwise apparent
at birth.
4/4/201813
Example of Tests
Are done :
galactosemia
sickle cell
disease
congenital
hypothyroidism

14. ِEX of Disorder diagnosed by NNS
galactosemia
sickle-cell anemia
4/4/201814

15. How is the neonatal screening done?
4/4/201815

16. 2.2.4- PMS in Saudi Arabia
years ago Saudi Arabia has
a high prevalence of
hereditary hemoglobin
disorders
4/4/201816
premarital screening in
Saudi Arabia markedly
reduced the number of at-
risk marriages, which may
considerably reduce the
genetic disease .
Now couples who are
going to married should
pass on this screening and
it’s provided free in
Accredited Premarital
Screening Centers

17. 2.2.4- Premarital Screening (PMS)
It’s done by taking blood sample from both of them
4/4/201817

18. What tests are done in Premarital Screening
genetic blood
diseases
sickle-cell
anemia
thalassemia
infectious
diseases
hepatitis
B, C
AIDS/HIV
4/4/201818
N.B: father cannot pass the infection directly to the baby but mother can
gives her baby the infection during delivery

19. ِEX of Diseases diagnosed by PMS:
sickle-cell anemia
4/4/201819

20. 2.2.5 - Preimplantation genetic diagnosis ( PGD ):
4/4/201820

21. Ovary stimulation
oocyte retrieval
sperm collecting
preimplantation genetic diagnosis
Transfer of the fetus
Steps of PGD :
1- giving some hormones
(FSH) as pills to stimulate
ovary to produce high
number of ovum
2- (ovum-pick up)
Collecting ovum from
uterus
3- Intracytoplasmic sperm
injection (ICSI) sperm is
injected into an egg to
fertilization in vitro
5- transformation of the
normal embryo after the
screening inside the uterus
*Description of each step is in the same color from the opposite site
1
2
3
4
5
4- screening of the
chances of genetic defects
within embryos
4/4/201821

22. 4/4/201822

23. 2.3- Vaccinating and supplementation
• Vaccinating :
• antigenic material to stimulate an
individual's immune system
• ex ; ( Vaccines against rubella to prevent
genetic defects in the fetus )
figure A
• Supplementation:
Are medicines which given before and
during pregnancy
ex ; (folic acid to prevent of
neural tube defect in newborn)
figure B,C
a b
c
4/4/201823

24. 3- Teratology and teratogens
• Teratogen:
• Any agent that can disturb the
development of an embryo or fetus
(cause a birth defect).
• About 4 to 5 percent of birth defects
are caused by exposure to a teratogen.
• Teratology:
⁃ Teratology is the science that studies birth defects , the
causes, mechanisms, and patterns of abnormal
development.
and its goals are:
(1) to describe and determine etiology ( ‫األمراض‬ ‫أسباب‬ ‫علم‬ ).
(2) to explore mechanisms involved in the production of
birth defects.
(3) to devise means of prevention .

26. 3.1-What is the harmful teratogen ?

27. 3.2-The effect of Teratogen
Teratogens may be do their effect
and cause these results:
• mutations
• chromosomal abnormality
• disturbances in cell division
• changes in nucleic acid composition and protein synthesis
• reduction of energy supply for embryonic and foetal
development
• disturbances of enzyme systems
• disturbances in the regulation of water and electrolyte
balance
• changes in membrane characteristics

29. They should also use
caution when taking
certain medications.
Some medications
that are normally safe
can cause serious
birth defects .
.
pregnant should start
taking folic acid
supplements before
conception To prevent
defects of the spine and
brain defects.
drug groups may cause birth defects in a developing fetus;
some antibiotic ,high doses of vitamin A,, ACE (angiotensin
converting enzyme) inhibitors
Many birth defects can’t be prevented, but there are some ways to
lower the risk of having a baby with a birth defect:
4-Maternal health during pregnancy

30. Exercise:
Moderate exercise is not
only considered safe for
pregnant women, it’s
encouraged and thought to
benefit both mom and
growing baby
Nutrition:
Eating a nutritious diet
during pregnancy is linked
to good fetal brain
development, , and it
reduces the risk of many
birth defects.
Maintaining a healthy
weight also helps reduce
the risk of complications
during pregnancy.
4-Maternal health during pregnancy

31. 4/4/201831

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