Genetic Counseling
Prevention of Genetic Diseases

Mohammad Al-Haggar, M.D.
Professor of Pediatrics & Genetics
Mansoura, Egypt
Prevention of Genetic Disease
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Genetic counseling

Genetic counseling
Genetic screening and testing (Carrier D)
Premarital counseling
Pre-implantation genetic diagnosis (PGD)
Prenatal diagnosis and selective abortion
Neonatal screening
Treatment of genetic disease
Family education
Genetic Counseling…is a communication process
which deals with problems associated with the
occurrence or the risk of recurrence of a birth defect or a
genetic disease in a family
…is the process of helping people understand and adapt to the medical,
psychological and familial implications of genetic contributions to disease.
This process integrates:
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Collection and interpretation of family and medical histories to assess the
chance of disease occurrence or recurrence
Education about inheritance, testing, management, prevention, resources
and research
Counseling to promote informed choices and adaptation to the risk or
condition.

Adopted from the NSGC website
Genetic Counseling Team
Primary Care
Provider
Pediatrician
Obstetrician
Internist
ENT etc.

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Maternal age ≥ 35
Consanguinity
Early Infant losses
Abnormal TRC
Fetal anomalies
Teratogen exposure
Role of Geneticist
First  Diagnosis (Category or Definitive);
pedigree construction
 Final  Decision; prevent or ameliorate
effects of genetic disease or birth defect
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First: Diagnosis
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Genetic or Not  if genetic (what type).
Inheritance pattern
Gene(s) involved
Available lab. tests
Available options
Final: Genetic Counseling
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Supportive…
Non-Directive…
Non-Judgmental…
Pre-implantation Genetic Diagnosis
(PGD)
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Prevention of Genetic Disease
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2.
3.
4.
5.

Genetic counseling
Neonatal screening
Carrier Detection  Mother (title of article)
Pre-implantation genetic diagnosis (PGD)
Education
Multi-D - US
(11-14 week scan)
AMNIOCENTESIS

PERFORMED ROUTINELY 16-20 WEEKS
Chorionic Villus
Sampling

Performed
>10 wks-12 weeks

Transcervical

Chromosome analysis
Risk 1/100-1/200

Transabdominal
Fetal Blood Sampling
“PUBS”
Carrier Testing (Mutation analysis)
Lethal AR diseases

• Common diseases e.g. Cystic fibrosis,
Thalassemia, Sickle cell anemia, FXS, TaySachs.
• IEMs  categorical diagnosis, metabolic
error, enzyme deficiency, single gene defect.
• Progressive neurologic deficit e.g.
Neuropathy, Myopathy, Ataxia, early onset
dementia.
THANK YOU
M. Al-Haggar, MD

m.alhaggar@yahoo.co.uk

Genetic counseling

  • 1.
    Genetic Counseling Prevention ofGenetic Diseases Mohammad Al-Haggar, M.D. Professor of Pediatrics & Genetics Mansoura, Egypt
  • 2.
    Prevention of GeneticDisease 1. 2. 3. 4. 5. 6. 7. 8. Genetic counseling Genetic counseling Genetic screening and testing (Carrier D) Premarital counseling Pre-implantation genetic diagnosis (PGD) Prenatal diagnosis and selective abortion Neonatal screening Treatment of genetic disease Family education
  • 3.
    Genetic Counseling…is acommunication process which deals with problems associated with the occurrence or the risk of recurrence of a birth defect or a genetic disease in a family …is the process of helping people understand and adapt to the medical, psychological and familial implications of genetic contributions to disease. This process integrates: • • • Collection and interpretation of family and medical histories to assess the chance of disease occurrence or recurrence Education about inheritance, testing, management, prevention, resources and research Counseling to promote informed choices and adaptation to the risk or condition. Adopted from the NSGC website
  • 4.
    Genetic Counseling Team PrimaryCare Provider Pediatrician Obstetrician Internist ENT etc. • • • • • • Maternal age ≥ 35 Consanguinity Early Infant losses Abnormal TRC Fetal anomalies Teratogen exposure
  • 5.
    Role of Geneticist First Diagnosis (Category or Definitive); pedigree construction  Final  Decision; prevent or ameliorate effects of genetic disease or birth defect 
  • 6.
    First: Diagnosis • • • • • Genetic orNot  if genetic (what type). Inheritance pattern Gene(s) involved Available lab. tests Available options
  • 7.
  • 14.
  • 15.
  • 16.
    Prevention of GeneticDisease 1. 2. 3. 4. 5. Genetic counseling Neonatal screening Carrier Detection  Mother (title of article) Pre-implantation genetic diagnosis (PGD) Education
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    Chorionic Villus Sampling Performed >10 wks-12weeks Transcervical Chromosome analysis Risk 1/100-1/200 Transabdominal
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    Carrier Testing (Mutationanalysis) Lethal AR diseases • Common diseases e.g. Cystic fibrosis, Thalassemia, Sickle cell anemia, FXS, TaySachs. • IEMs  categorical diagnosis, metabolic error, enzyme deficiency, single gene defect. • Progressive neurologic deficit e.g. Neuropathy, Myopathy, Ataxia, early onset dementia.
  • 32.
    THANK YOU M. Al-Haggar,MD m.alhaggar@yahoo.co.uk

Editor's Notes

  • #5 Genetic Counselor is a medical professional who understand the bases of genetics: Interitance (Traditional and non-traditional) Mutations (molecular genetics) Link between.
  • #7 Teratogenesis or mutagenesis// Inheritance (traditional or non-traditional) // Single gene defect or chromosomal: Chromosomal  Pregnant with H. Down or abnormal TRC, Woman with balanced translocation, FXS (MR, Premature ovarian failure or low fertility ↑FSH). Single gene defect  Carrier consanguineous parents for lethal AR.
  • #8 Allow families to make decisions based on their own personal, cultural, ethical and social beliefs Emphasize the fact that there is nothing that they have done that caused the fetal abnormalities
  • #10 Unlucky lady, non-consang. Husband, two male neonates died at 1-2 weeks age by ? Sepsis or ill-neonate CP  encrourage 3rd baby was male followed immediate developed hyper NH3  IEM, UCD  Aminogram  localize OTC deficiency  confirmed by enzyme assay (liver biopsy) and gene testing (OTC gene).
  • #11 Unlucky lady, non-consang. Husband, two male neonates died at 1-2 weeks age by ? Sepsis or ill-neonate CP  encrourage 3rd baby was male followed immediate developed hyper NH3  IEM, UCD  Aminogram  localize OTC deficiency  confirmed by enzyme assay (liver biopsy) and gene testing (OTC gene).
  • #12 Unlucky lady, non-consang. Husband, two male neonates died at 1-2 weeks age by ? Sepsis or ill-neonate CP  encrourage 3rd baby was male followed immediate developed hyper NH3  IEM, UCD  Aminogram  localize OTC deficiency  confirmed by enzyme assay (liver biopsy) and gene testing (OTC gene).
  • #27 Heterozygous parents  Homozygous probands  Prenatal, pre-symptomatic, PGD: Source of DNA  before IVF, Amniocentesis (possible contamination), non-invasive (fetal DNA circulating in maternal blood). Cystic fibrosis  Caucasian couples (ACOG, 2001). IEMs  all Ashkenazi Jews (ACMG 2008)  Tay Sachs, Canavan disease, familial dysautonomia, Fanconi anemia (Group C), Bloom syndrome, Gaucher disease, Niemann-Pick (Type A) and mucolipidosis IV. Fragile X-syndrome (ACMG 2004) for: Families with  reported unidentified MR, Known carrier mothers, Women with fertility problems (↑ed FSH) especially if they have FH of premature ovarian failure, FXS, or male or female relatives with unidentified MR. Factor V Leiden carrier screening (ACMG 2001, 2006)  for situations suggestive of thrombophilia especially IF: Relatives having factor V Leiden. Recurrent pregnancy loss or unexplained severe preeclampsia, placental abruption, IUGR, or stillbirth.
  • #32 Some Dysmorphic syndromes due to single gene defects  Seckle// William, Digeorge// CDG// Ehler Danlos, Cutis laxa