Chapter 11 Common Childhood-Onset Genetic Disorders

Chapter 11: Common Childhood-Onset Genetic Disorders ____ 1. Which ethnic group has the highest incidence of sickle cell disease (SCD)? C. African Americans ____ 2. Which type of testing is most commonly used to diagnose sickle cell disease? B. Hemoglobin electrophoresis ____ 3. Which specific type of genetic problem causes sickle cell disease? D. Single-nucleotide polymorphism ____ 4. How is sickle cell trait different from sickle cell disease? A. People with sickle cell disease are homologous for the mutation, whereas those with sickle cell trait are heterozygous for the mutation. ____ 5. Which feature or factor is the best predictor for delay of complications in a person who has sickle ____ 6. How does the drug Endari reduce the manifestations of sickle cell disease? C. Reducing oxidate stress and increasing the life span of red blood cells ____ 7. What health advantage does sickle cell trait or disease confer on the person who has it? D. Decreased risk for malaria ____ 8. A woman whose hemoglobin S levels are less than 1% has a brother with sickle cell disease, and ____ 9. Which ethnic group has the highest incidence of cystic fibrosis (CF)? cell disease (SCD)? B. 20% or greater of HbF both parents have been diagnosed as carriers for the disorder. She asks what her risks are of having a child with sickle cell disease. What is the best response? A. “Because you do not have the trait, you cannot have a child with sickle cell disease regardless of your partner’s sickle cell status.” D.E uropean Americans ____ 10. Which type of testing is most commonly used to diagnose cystic fibrosis (CF)? C. Sweat chloride analysis ____ 11. Which relative of a patient who has cystic fibrosis has the correct risk for being a cystic fibrosis carrier? B. Mother 50% ____ 12. Which tissues are most commonly affected by mutation of the CFTR gene? C. Lungs and pancreas ____ 13. What is the most likely explanation for the variability in expression of disease severity for cystic fibrosis? B. The specific CFTR gene mutation inherited ____ 14. What health advantage does cystic fibrosis confer on the person who has it? D. Decreased risk for typhoid ____ 15. Which statement regarding Duchenne muscular dystrophy (DMD) is true? C. Because DMD is X-linked recessive, males are affected, and females are carriers. ____ 16. Why does Duchenne muscular dystrophy (DMD) have poor reproductive fitness? A. Most affected individuals typically do not have children. ____ 17. What is the explanation for creatine kinase (CK) levels in a 14-year-old boy with Duchenne muscular dystrophy being much lower now than they were 5 years ago? C. Most of the muscle tissue has already been destroyed. ____ 18. Which additional health problem commonly develops in boys with Duchenne muscular dystrophy? D. Chronic heart failure ____ 19. A 21-year-old woman who has two brothers with Duchenne muscular dystrophy asks whether carrier status testing is appropriate for her. What is the best response? B. “Testing could be beneficial because your risk for being a carrier is approximately 50%. ____ 20. Zoe, a 20-year-old woman, shows signs of mild muscle weakness. She has two first cousins on her mother’s side who died of Duchenne’s muscular dystrophy (DMD). Which explanation regarding Zoe’s situation is most likely? A. Zoe is a heterozygote showing partial expression ____ 21. How is hemophilia A (classical hemophilia) different from hemophilia B? C. The clotting factor problem in hemophilia B is a deficiency of factor IX rather than factor VIII. ____ 22. Which statement regarding classic hemophilia is true? C. Because hemophilia is X-linked recessive, males are affected, and females are carriers. ____ 23. Which type of testing is most commonly used to diagnose classic hemophilia? D. Factor VIII levels ____ 24. A 12-year-old girl was diagnosed with von Willebrand disease (VWD) when she developed profound anemia from very heavy menstrual periods. Her levels of von Willebrand (vWf) factor are normal. What specific type of von Willebrand disease is she most likely to have? B. Type 2 VWD ____ 25. Which statement regarding type 1 von Willebrand disease (VWD) is true? A. Incomplete penetrance is common. ____ 26. Which form of von Willebrand disease (VWD) is most often diagnosed in early childhood? C. Type 3 VWD ____ 27. Which statement about achondroplasia is true? C. The protein impaired by the mutation is the receptor for fibroblast growth factor. ____ 28. Which health problem occurs at a higher rate among children with achondroplasia than among the general population? D. Sudden infant death syndrome ____ 29. A son with achondroplasia is born to parents with no family history of the disease. What is the most likely explanation for the son’s disorder? C. The gamete of one parent had a spontaneous mutation. ____ 30. Which phenotypic feature associated with achondroplasia has variable expression? D. Hydrocephaly ____ 31. Which factor has the greatest genetic influence in the development of type 1 diabetes mellitus? A. Inheritance of the HLA-DR or HLA-DQ tissue types ____ 32. For individuals who have increased genetic susceptibility for type 1 diabetes, what is the most common environmental trigger for disease expression? D. Viral infection ____ 33. Which problem or symptom is associated with type 1 diabetes but not with type 2 diabetes? A. Insulitis ____ 34. Which result of genetic/genomic variation has the most support as a cause of asthma? C. Increased inflammatory responses to environmental triggers