ATI RN
Genetic Pediatric Questions
Question 1 of 5
SMOH gene located in pseudoautosomal in Y chromosome, do you expect that it will be located in 46 XX?
Correct Answer: A
Rationale: Yes (A), pseudoautosomal regions (PAR) are on both X and Y. Rationale: PAR genes (e.g., SHOX, not SMOH—a typo?) are homologous on X and Y, present in 46, XX females, unlike Y-specific genes.
Question 2 of 5
Possibility of combinations for diploid cell with 10 chromosomes?
Correct Answer: D
Rationale: 2^n where n=5 (haploid from 2n=10) gives 32 (D). Rationale: Independent assortment of 5 pairs yields 2^5 = 32 gamete combinations.
Question 3 of 5
You are asked to consult about a 2-month-old girl with hypotonia, seizures, and an elevated plasma lactate (8 mM/L, normal <2). Brain MRI shows a thin corpus callosum but no other abnormalities. You suspect pyruvate dehydrogenase deficiency. Which of the following is the most likely mode of inheritance in this infant?
Correct Answer: C
Rationale: Pyruvate dehydrogenase deficiency (PDH) is often autosomal recessive (C), though X-linked forms exist. Rationale: E1 subunit mutations (PDHA1, X-linked) are common, but autosomal recessive (other subunits) fits sporadic cases in females without male bias; symptoms match metabolic defect.
Question 4 of 5
Matching: Vulvovaginitis - Associated
Correct Answer: A
Rationale: ‘Associated’ is vague, but Enterobiasis (A, pinworms) is commonly linked to vulvovaginitis in children via perineal migration. Rationale: Molluscum (B) and lice (C) are skin-specific; Shigella (D) and Streptococcus (E) cause bacterial vaginitis, but pinworms are a frequent pediatric association.
Question 5 of 5
Mastodynia is best characterized as
Correct Answer: D
Rationale: Mastodynia (breast pain) is typically cyclical, related to the menstrual cycle; ‘unrelated’ (D) is incorrect, but options suggest cyclical is absent, making D the best fit. Rationale: Cyclical mastodynia peaks premenstrually; noncyclical (C) is less common and not size-dependent (A).