A genetic disease is found in a family that affects the immune system, lungs, heart, and kidneys. A DNA analysis of several affected and unaffected family members determines that the disease is caused by a mutation in a single gene. What type of inheritance pattern is shown in this disease? (1 point)
a. incomplete dominance
b. pleiotropy
c. codominance
d. polygenic trait
b. pleiotropy
Pleiotropy occurs when one gene influences two or more seemingly unrelated phenotypic traits. Since the disease affects multiple systems (immune, lungs, heart, kidneys) and is caused by a mutation in a single gene, this fits the description of pleiotropy. The inheritance pattern (autosomal dominant, autosomal recessive, X-linked, etc.) cannot be determined from the information provided.