Prenatal diagnostics

Question 1

What is spina bifida?

Answer 1

Spina bifida is a condition that affects the spine and is usually apparent at birth. It is a type of neural tube defect (NTD). Spina bifida can happen anywhere along the spine if the neural tube does not close all the way.

1. SB occulta: failure of vertebral arches to form.
2. SB aperta: failure of neural tube closure and vertebral arches do not form properly.
   
   • Meningocele: fluid-filled meninges protrude
   • Myelomeningoceel: neural tissue protrude
   • Rachischisis: no developed neural tube

This condition can be prevented by follic acid inteke, and it can be detected by ultra-sound and amniocentesis, due to the presence of high levels of α-fetoprotein.
There are various treatment for the SB, depending on the type of the disease:
1. Operation postnatally
- Meningocele in 1st year
- Myelomeningocele first days
2. Prenatal operation, only possible with myelomeningocele.

Question 2

What are the different molecular techniques used to detect chromosomal abnormalities?

Answer 2

1. Maternal/Paternal assessment
   
   • family history
   • physical exam
2. Maternal vaccination
3. Maternal/Paternal screening
   
   • HIV
   • genetic disorders
4. Counsling
   
   • folic acid
   • no teratogens

If we want to perform a pre-conception genetic diagnostic, we can:

• DNA testing to see if parents are carriers
• IVF/intracytoplasmic sperm injection to see if implanted embryos are healthy

If we want to perform a post-conception diagnostic, we can:

• nuchan scan to see if there’s fluid collected in the neck
• maternal serum
• amniocentesis
• chorionic villi

Question 3

What are association diseases? And syndromes?

Answer 3

Associated disease are a group of anomalies with high co-occurence; syndromes are a group of anomalies with specific and known causes