Assessment and Screening Flashcards
1
Q
What is syndactyly?
A
Fusion of digits
2
Q
How can dysmorphic features be assessed?
A
Measurement compared to centiles of patients other measurements
3
Q
How is a sample taken for pre-implantation genetic diagnosis?
A
A single cell is removed at day 3 post-fertilization from a 6-10 cell embryo in IVF
4
Q
How is pre-implantation genetic diagnosis carried out?
A
FISH or PCR to determine:
- sex (if X-linked)
- specific mutation
- mutation-associated haplotype
- chromosomal abnormality
5
Q
What are the pros to pre-implantation genetic diagnosis?
A
- implantation of unaffected embryos
- TOP unnecessary
6
Q
What are the cons to pre-implantation genetic diagnosis?
A
- possible long wait
- not available to all women
- difficulty with multiple visits and procedures
- successful births <20% per oocyte
7
Q
When are genetic screening tests offered?
A
During:
- pregnancy
- neonatal period
- adulthood
8
Q
What are the main principles of a screening programme?
A
- should be a clearly defined disorder
- with appreciable frequency
- advantages to early diagnosis
- few false positives
- few false negatives
- benefits outweigh the costs
