ATI RN
Common Pediatric Genetic Disorders Questions
Question 1 of 5
Dysgerminomas of the ovaries are usually associated with
Correct Answer: B
Rationale: Dysgerminomas, germ cell tumors, are linked to X-Y gonadal dysgenesis (B). Rationale: XY females (e.g., Swyer syndrome) have dysgenetic gonads prone to malignancy; Turner (C) and Noonan (A) involve XO or other defects, less associated.
Question 2 of 5
Which of the following is an X-linked dominant inheritant disease?
Correct Answer: D
Rationale: Rett syndrome is XLD (MECP2 gene). Rationale: DMD (A) is XLR; Gaucher (B) is AR; Angelman (C) is imprinting; cat eye (D) is chromosomal.
Question 3 of 5
Disorders caused by expansion of trinucleotide repeats include all the following EXCEPT
Correct Answer: B
Rationale: Ataxia-telangiectasia (B) is due to ATM mutations, not trinucleotide repeats. Rationale: Fragile X (A), Huntington (C), myotonic dystrophy (D), and Friedreich (E) involve CGG, CAG, CTG, GAA repeats.
Question 4 of 5
Consanguinity may increase the chance that a child will be born with a rare autosomal recessive (AR) condition. The risk of first cousins producing a child with an AR disorder is
Correct Answer: A
Rationale: First cousins share 1/8 genes; AR risk is 1/4 if both carriers, total ~1/16 (A). Rationale: General population risk is lower; consanguinity amplifies rare allele sharing.
Question 5 of 5
A 15-day-old baby with Down syndrome, during routine blood testing found to have high leukocyte count (34,000), the baby otherwise is asymptomatic. Of the following, the MOST appropriate advice /action is
Correct Answer: D
Rationale: Transient leukemoid reaction in DS newborns is common and benign (D). Rationale: Resolves spontaneously; leukemia (A) is a risk but not at 15 days without symptoms.