2. 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
3. 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
4. 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
5. Role of Geneticist
First Diagnosis (Category or Definitive);
pedigree construction
Final Decision; prevent or ameliorate
effects of genetic disease or birth defect
Genetic Counselor is a medical professional who understand the bases of genetics:
Interitance (Traditional and non-traditional)
Mutations (molecular genetics)
Link between.
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.
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
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).
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).
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).
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.
Some Dysmorphic syndromes due to single gene defects Seckle// William, Digeorge// CDG// Ehler Danlos, Cutis laxa