ppt

1. Topic: Medical and genetic
counseling and prevention
of hereditary diseases
Mirzayeva N.S

2. “We used to think that stars determine our
fate. Now we know that in many ways our
destiny is our genes, ”
Nobel laureate James Watson.

3. Genetic counseling is a specialized type of
medical care for the population aimed at the
prevention of hereditary diseases.
The purpose of genetic counseling
- prevention of the birth of children with incurable
congenital diseases
- in the general population sense is the reduction
of the burden of pathological heredity,
- and the purpose of a separate consultation is to
help the family in making the right decision on
family planning

4. BASIC COMPONENTS OF MEDICAL-GENETIC
CONSULTING

5. The tasks of genetic counseling are:
1) diagnosis of a hereditary disease;
2) determination of the nature of inheritance;
3) calculation of repeated genetic risk;
4) determination of the method of prevention;
5) an explanation of the values of risk, methods
of prevention, treatment and rehabilitation;
6) referral of patients to specialized medical
institutions for counseling on problems of
treatment and rehabilitation.

6. • Prospective counseling - counseling
before pregnancy or in its early stages
• Retrospective counseling is carried out
after the birth of a sick child (congenital
malformations, delayed physical
development and mental retardation)
regarding the health of future children.

7. Newborn screening
Congenital hypothyroidism is a violation of the structure of the thyroid
gland and defects in the biosynthesis of hormones of this gland.
Phenylketonuria is a genetic disease associated with a
deficiency or lack of an enzyme that is necessary for the
digestion of phenylalanine into torosin.
Cystic fibrosis - a serious hereditary disease,
accompanied by an increase in the viscosity of the
secretions of the glands
Adrenogenital syndrome - this disease is caused due to the absence of one
of the enzymes responsible for the synthesis of cortisol
Galactosemia is a metabolic disorder; there is no enzyme that converts
galactose to glucose.
For 4-5 days, the child takes blood

8. Genetic counseling is recommended above all:
• Women over 35;
• Families where there have already been births of
children with congenital malformations;
• Women who have miscarriages, especially in the early
stages (up to 12 weeks);
• Women with endocrine disorders;
• Families living in environmentally disadvantaged areas in
contact with chemical and radiation mutagens;
• Pregnant women with deviations detected during
ultrasound and biochemical examinations.

9. Stages of genetic counseling
1. Diagnostics
Counseling always begins with a clarification
of the diagnosis of hereditary disease, since
an accurate diagnosis is a prerequisite for any
consultation. Clarification of the diagnosis in
the medical genetic consultation is carried out
using genetic analysis. Moreover, in all cases without exception, the
genealogical method of research is used.
2. ForecastingGenetic risk can be determined either by theoretical
calculations using genetic analysis methods and variation statistics, or
using empirical data
3. Conclusion.
To achieve the goal of counseling when talking with patients, one should
take into account the level of their education, the socio-economic
situation of the family, personality structure, and family relationships.
The interpretation of risk must be tailored to each case individually.

10. Prenatal diagnosis of hereditary
diseases
- A comprehensive, rapidly developing field of
medicine using ultrasound diagnostics, surgical
equipment and laboratory methods. Methods of
perinatal diagnosis can be divided into three
groups:
- sifting,
- non-invasive
- invasive (with subsequent laboratory
diagnosis).

11. Screening laboratory methods include the
determination of substances in the blood serum of a
pregnant woman that are called serum markers of the
mother
Prenatal screening of trisomy II trimester of
pregnancy is performed to assess the likelihood of the
most common fetal abnormalities - trisomy 21 (Down
syndrome), trisomy 13 (Patau syndrome), trisomy 18
(Edwards syndrome) and neural tube defect between
14 and 22 weeks of pregnancy.

12. • The following serum markers for 15-20 weeks are
determined
• α-fetoprotein (AFP),
• human chorionic gonadotropin (hCG),
• unbound estriol (EZ)
• It is very important to know exactly the gestational
age of the fetus, since the levels of AFP, hCG and
free estriol in the blood differ at different weeks of
pregnancy.

13. Alpha-fetoprotein is produced in the embryonic yolk
sac, liver and intestinal epithelium of the fetus, its
level depends on the condition of the gastrointestinal
tract, fetal kidneys and the placental barrier. He takes
an active part in the full development of the fetus. In
the mother's blood, its concentration gradually
increases from the 10th week of pregnancy and
reaches a maximum at 30-32 weeks.
ACE decline - suspected trisomy
An increase in ACE - a suspicion of impaired
development of the neural tube

14. Human chorionic gonadotropin (hCG) is produced in
the fetal membrane of the human embryo. It is an
important indicator of the development of pregnancy
and its abnormalities. The hCG level reaches a
maximum at the 10-11th week, and then gradually
decreases. By this indicator, it is possible to judge
the successful course of pregnancy and identify
violations of the development of the fetus.
HCG reduction - the threat of miscarriage
Increased hCG in combination with a decrease in
AFP and EZ - suspected Down syndrome

15. Free estriol is the main estrogen of pregnancy and is
of great importance for the normal development and
functioning of the fetoplacental complex. Its
concentration rises since the formation of the
placenta and progressively increases with the course
of pregnancy.
A low concentration of free estriol in combination with
high rates of beta-hCG and alpha-AF is associated
with an increased risk of intrauterine growth
retardation and complications of the third trimester of
pregnancy (premature placental abruption
andпреэклампсии).

16. Recommended Pregnancy Methods and Tests
Pregnancy
(weeks)
Methods and Tests
First visit (as soon
as possible)
Determination of hemoglobin content and blood hematocrit.
Urinalysis, screening for urinary tract infections. Determination of
blood group and Rh-phenotype, titer of anti-HBs antibodies in Rh-
negative women. Anti-rubella antibody titer Wasserman reaction
Cervical smear cytology Determination of HBs antigen in the blood
8-18th
Ultrasound examination of the fetus and placenta Amniocentesis or
chorionic biopsy according to indications
16-18th
The level of alpha-fetoprotein, as well as chorion-gonadotropin and
free estriol in the blood
26- 28th
Screening for diabetes mellitus, re-determination of hemoglobin and
blood hematocrit, urine analysis for protein, sugar, non-stress test
28th
Re-examination of the titer of anti-RH antibodies in Rh-negative
pregnant women, prophylactic administration of anti-RH (0) -
immunoglobulin
32- 36th
Ultrasound of the fetus, determination of hemoglobin, blood
hematocrit, bacteriological examination of a vaginal smear

18. Non-invasive methods
• – These are methods for
examining the fetus without
surgical intervention. Currently,
they include only ultrasound.

19. Ultrasound during pregnancy is a screening
method of examination, i.e. it is carried out
without fail for every pregnant woman. According
to the order of the Ministry of Health “On
improving prenatal diagnosis in the prevention of
hereditary and congenital diseases in children”, a
three-time ultrasound screening was approved:
the first in terms of 10 to 14 weeks;
the second - from 20 to 24 weeks;
the third - from 32 to 34 weeks.

21. Invasive methods of perinatal
diagnosis
– these are methods for obtaining
samples of cells and tissues of the
embryo, fetus, and provisional organs
(placenta, membrane) with subsequent
study of the obtained materials

22. Amniocentesis
-- This is a study that is carried out by puncturing a thin needle
with the abdominal wall, uterus and bladder to sample
amniotic fluid. Genetic amniocentesis is a study of the
chromosome set of the fetus, it is usually carried out between
the 15th and 20th weeks.

23. Cordocentesis
Cordocentesis – blood sampling from the umbilical cord is
carried out from the 20th week of pregnancy. The procedure is
carried out under the supervision of ultrasound. Blood
samples are an object for cytogenetic (lymphocytes are
cultivated), molecular genetic and biochemical methods for the
diagnosis of hereditary diseases.

24. Chorion and placental biopsy
Chorion - and placental biopsy have been used since
the late 80s. These methods are used to obtain a
small amount of chorionic villi or pieces of the
placenta during the period from the 8th to the 16th
week of pregnancy. There is no fundamental
difference between the indications for use of these
two biopsy methods.

25. • Fetal tissue biopsy
• A biopsy of fetal tissues as a diagnostic procedure is
carried out in the second trimester of pregnancy
under the supervision of an ultrasound scan. For the
diagnosis of severe skin lesions (ichthyosis,
epidermolysis), a biopsy of the fetal skin is done with
a subsequent pathomorphological study.

26. • Fetoscopy
• Fetoscopy (insertion of the probe and examination of the fetus) with
modern flexible optical technology does not present great difficulties.
However, the method of visual examination of the fetus to identify
congenital malformations is used only for special indications. It is
carried out on the 18-19th week of pregnancy.

27. According to the degree of threat (risk) of re-
manifestation of hereditary diseases in the family,
they are divided into 3 groups:
1. diseases with a high degree of genetic risk (1: 4), which include
diseases with autosomal dominant, autosomal recessive and sex-
linked inheritance;
2. diseases with a moderate degree of genetic risk (less than 1: 10); these
include hereditary diseases caused by fresh mutations, as well as
chromosomal diseases and diseases with a polygenic type of
inheritance, i.e. a significant part of congenital malformations and
hereditary diseases developing against a genetically unfavorable
background;
3. diseases characterized by a slight risk of re-manifestation or a
complete lack of risk.

28. THANK YOU FOR THE
ATTENTION!