Exam 11: Common Childhood-Onset Genetic Disorders

Awoman whose hemoglobin S levels are less than 1% has a brother with sickle cell disease, and 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?

Which phenotypic feature associated with achondroplasia has variable expression?

For individuals who have increased genetic susceptibility for type 1 diabetes, what is the most common environmental trigger for disease expression?

Which statement regarding Duchenne muscular dystrophy (DMD) is true?

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).Whichexplanation regarding Zoe's situation is most likely?

Which statement about achondroplasia is true?

Which ethnic group has the highest incidence of cystic fibrosis (CF)?

Which type of testing is most commonly used to diagnose cystic fibrosis (CF)?

What health advantage does cystic fibrosis confer on the person who has it?

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?

How is hemophilia A (classical hemophilia) different from hemophilia B?

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?

Which factor has the greatest genetic influence in the development of type 1 diabetes mellitus?

Which problem or symptom is associated with type 1 diabetes but not with type 2 diabetes?