Chromosomal abnormalities Practice Questions
20 free Chromosomal abnormalities practice questions for the USMLE Step 1, each with the correct answer and a detailed explanation. Open any question below, or take the full set as an interactive quiz.
Questions
20 questions
All Chromosomal abnormalities questions
- Q1. A newborn presents with hypotonia, upslanting palpebral fissures, a single palmar crease, and a congenital heart defect. Cytogenetic analysis confirms trisomy…
- Q2. A 3-year-old child has severe intellectual disability, microcephaly, and a high-pitched crying sound. Karyotype shows a partial deletion on chromosome 5p. Whic…
- Q3. Which chromosomal abnormality results from a reciprocal translocation between the long arms of chromosomes 14 and 21?
- Q4. A patient with short stature, streak ovaries, webbed neck, and coarctation of the aorta likely has which chromosomal finding?
- Q5. A teenager with tall stature, small testes, gynecomastia, and reduced facial hair undergoes genetic testing. The likely result is:
- Q6. Microarray testing on a child with intellectual disability and elfin facies reveals a deletion on chromosome 7q11.23. Which condition is this?
- Q7. A newborn with congenital heart disease and thymic aplasia is diagnosed with 22q11 deletion. Which mechanism caused this abnormality?
- Q8. A child with severe hypotonia, obesity, hyperphagia, and small hands/feet likely has which chromosomal mechanism causing the disease?
- Q9. A woman with multiple miscarriages is found to carry a balanced Robertsonian translocation. What is her chromosomal composition?
- Q10. A child presents with hypertelorism, cleft lip/palate, seizures, and a deletion on chromosome 4p. Which condition is this?
- Q11. A patient with trisomy 18 presents with overlapping fingers, rocker-bottom feet, and cardiac abnormalities. What meiotic error most commonly causes this condit…
- Q12. A karyotype shows 69,XXX in a spontaneously aborted fetus. Which abnormality does this represent?
- Q13. A newborn female has ambiguous genitalia, cleft palate, and holoprosencephaly. Genetic testing confirms trisomy 13. What is the chromosomal basis?
- Q14. A lab report shows the presence of an isochromosome of the X chromosome. This finding is most associated with which condition?
- Q15. Which chromosomal finding is most consistent with chronic myelogenous leukemia (CML)?
- Q16. A newborn with micrognathia, low-set ears, and clenched fists is diagnosed with Edwards syndrome. What karyotype confirms this condition?
- Q17. A child presents with ataxia, seizures, and inappropriate laughter. Genetic testing reveals maternal imprinting defect with paternal uniparental disomy. Which…
- Q18. A karyotype reveals mosaicism with two cell lines: 46,XX and 47,XX,+21. Which statement is correct?
- Q19. A fetus has cystic hygroma and hydrops fetalis. Karyotype reveals 45,X. Which mechanism explains the monosomy?
- Q20. A neonate presents with polydactyly, microcephaly, and congenital heart disease. Genetic testing shows meiotic nondisjunction. Which trisomy is most likely?