Chromosomal Microarray and Exome Testing – Board-Style Questions

What this deck covers

chromosomal microarray and exome testing in 18 board-style clinical cases with worked explanations. Each case gives you a clinical vignette, four options, the correct answer, and an explanation of why each of the other three is wrong, with the guideline or textbook it follows named on the answer.

Board-style teaching questions for paediatricians and trainees preparing for paediatric board, MRCPCH and licensing examinations. Written from published guidelines and standard paediatric textbooks, with the source named on every answer.

The 18 cases, in order

1. What it cannot see
2. Mother has it too
3. Long identical stretches
4. Two from one side
5. Three samples, one answer
6. A year later
7. The wrong tool
8. More than they asked
9. Days, not months
10. How big is too big?
11. Where did it come from?
12. The wrong first test
13. Making an uncertain report useful
14. Blood said no
15. A figure for the family
16. After a third loss
17. After the report is issued
18. Too small to see

Diagnoses and management options tested

Across the 18 cases you are asked to choose between options such as: A large deletion involving several genes on one chromosome arm, It is probably harmless, since a well parent carries the same change, A chromosome that has been lost and then duplicated again in error, A large segment of chromosome 15 has been deleted in him, Reading both parents alongside him separates new from inherited, Repeat the same exome on a fresh blood sample taken from the boy, A change in a single letter of a well-known disease gene, The certainty that the muscle disorder will now be explained, A result in days, which can change what intensive care is offered, The number of letters of DNA that have been lost from it, Quote a low recurrence risk without testing either of the parents, A whole chromosome present in three copies in every cell, Whether the change tracks with illness through the wider family, The child has no chromosome disorder of any kind at all.

Clinical pearls from this deck

• An array counts material; it cannot see a swap.
• A change a well parent carries is usually harmless.
• Long homozygous runs: hunt for recessive disease.
• One chromosome, no heterozygosity: both from one parent.
• Sequence the trio: parents make the child’s result readable.
• Stored sequence can be re-read as knowledge grows.

Work through the deck once for recognition, then again a week later to test yourself — each question gives the answer and explains why every other option fails.

More from this system: all genetics and metabolic case decks · pediatric reference values.