The nurse at the geneticist's office is caring for a 22-year-old ...

[DelorasTo]

The nurse at the geneticist's office is caring for a 22-year-old patient who might have a mitochondrial mutation. Which patient statements are most consistent with this information?
 
  Select all that apply.
  1. My dad was unable to hear normally after the age of 15.
  2. My mom and my sister are really little when compared to the rest of my family.
  3. My mom and my grandmother have trouble with seizures.
  4. My dad and my uncle both had heart attacks when they were in their 40s.
  5. I have some trouble walking and my muscles seem to be getting weaker.

Question 2

The parents learn that their newborn has the CFTR gene located on chromosome 7. During counseling, what should the parents be told about the ways that this genetic alteration may be expressed as the child grows?
 
  Select all that apply.
  1. The child develops normally without any clinical manifestations associated with cystic fibrosis.
  2. The patient is placed on a lung transplant list.
  3. The patient receives bilateral mastectomies.
  4. The patient is counseled about the increased risk of developing Alzheimer disease.
  5. The child exhibits some mild signs and symptoms associated with cystic fibrosis.

[tanna.moeller]

Answer to Question 1

Correct Answer: 2, 3, 5
Mitochondrial genes and any diseases due to DNA alterations on those genes are transmitted through the mother in a matrilineal pattern. An affected female will pass the mtDNA mutation to all of her children. However, an affected male will not pass the mtDNA mutation to any of his children. The patient's mother and sister have small statures and this may be related to a mitochondrial mutation. The patient's mother and grandmother have a history of seizures and this can indicate that they are experiencing clinical manifestations associated with mitochondrial mutations. The patient's development of ataxia and hypotonia is concerning for the nurse to learn about because this can be associated with mitochondrial mutations. The patient's father developed deafness at an early age and while this may be the result of a mitochondrial genetic alteration, it is not necessarily as concerning to learn about because the father will be unable to pass this mitochondrial mutation to his child. The patient's father and uncle experienced myocardial infarctions at abnormally early ages and while this may be the result of a mitochondrial mutation, it is not as concerning because the father will be unable to pass this mitochondrial mutation to his child.

Answer to Question 2

Correct Answer: 1, 2, 5
The CFTR gene is a very large gene that is located on chromosome 7. Many different mutations of the CFTR gene have been reported to be associated with the disease. The area of the CFTR gene that controls mucous production can have more than 300 different gene alterations resulting in a variety of symptoms that range from no clinical manifestations at all to severe problems. The patient with severe cystic fibrosis may be placed on a lung transplant list. The child may experience a mild form of cystic fibrosis. The CFTR gene does not necessarily increase the patient's risk for developing breast cancer or Alzheimer disease.