A father and mother are carriers of phenylketonuria (PKU). Their 2-year-old daughter has the condition. The couple tells the nurse that they are having a second baby. Because their daughter has PKU, they are certain that this baby will not be affecteWhich response by the nurse is the most accurate?

Correct Answer: C

Rationale: Each child conceived by this couple has a one-in-four chance of being affected with the PKU disorder. This couple still has an increased likelihood of having a child with PKU; having one child already with PKU does not guarantee that they will not have another. These parents need to discuss their options with their physician. However, an opportune time has presented itself for the couple to receive correct teaching about inherited genetic risks. No correlation exists between gender and inheritance of the disorder, because PKU is an autosomal recessive disorder.

Correct Answer: B

Rationale: The majority of the 0.1% genetic variations are found within and not among populations. Most human genes produce at least three proteins. The project's research has been very valuable in the identification of genes involved in disease and in the development of genetic testing. There are 20,500 genes in the human genome; scientists originally estimated more than 50,000 genes. Human genes are more efficient than the genes in other species, thereby increasing the human genetic complexity.

Correct Answer: B

Rationale: This mother will likely experience a disruption in the family process related to the birth of a baby with an inherited disorder. Therefore, the probable nursing diagnosis for this family is 'Interrupted family processes.' Women commonly experience 'body image disturbances in the postpartum period'; however, this nursing diagnosis is unrelated to giving birth to a child with Down syndrome. The mother will likely have a mix of emotions that may include anxiety, guilt, and denial, but this nursing diagnosis is not the most essential for this family. 'Risk for injury' is not an applicable nursing diagnosis.

Correct Answer: B

Rationale: Aneuploidy is an abnormality of number that is also the leading genetic cause of mental retardation. Chromosomal abnormalities occur in fewer than 1% of newborns. Down syndrome is the most common form of a trisomal abnormality, an abnormality of chromosome number (47 chromosomes). Unbalanced translocation is an abnormality of chromosomal structure that often has serious clinical effects.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.