ATI RN
Genetic Disorders in Pediatrics Questions
Question 1 of 5
A 2-year-old girl with history of delayed speech, lonely play, and special hand movement (hand washing posture), the parents are healthy relative couple. The genetic cause of this disorder is MOST likely due to
Correct Answer: C
Rationale: Rett syndrome (hand-washing, regression) is often a de novo mutation (C) in MECP2 (XLD). Rationale: Healthy parents and consanguinity reduce carrier likelihood (A, B); not chromosomal (D).
Question 2 of 5
Of the following, the study that is MOST useful in diagnosis of an aneuploidy is
Correct Answer: A
Rationale: Karyotyping (A) directly visualizes aneuploidy (e.g., trisomy 21). Rationale: FISH (B) confirms specific regions; microarray (C) detects microdeletions, not whole chromosome changes.
Question 3 of 5
A young parents with Down syndrome baby with Robertsonian translocation. Both did a chromosomal karyotype study. Of the following the MOST likely result is
Correct Answer: B
Rationale: Maternal Robertsonian translocation (e.g., t(14;21)) is more common in DS (B). Rationale: Maternal age and translocation risk skew higher; one parent is typically the carrier.
Question 4 of 5
All the following are characteristic features of Williams syndrome EXCEPT
Correct Answer: D
Rationale: Williams syndrome (7q11.23 deletion) includes hypercalcemia (A), elfin face (B), blue irides (C), and friendly personality (E); IQ is typically low (D is false). Rationale: Mild intellectual disability is common.
Question 5 of 5
FISH in genetic testing is best described as
Correct Answer: D
Rationale: Fluorescence In Situ Hybridization (FISH) uses fluorescent probes to locate specific DNA sequences on chromosomes, identifying gene locations or chromosomal abnormalities. It doesn’t involve RNA prep, enzyme assays, buccal scraping, or fibroblast inhibition.