The doctor says that Lydia’s baby has a disorder caused by one single gene. What does the baby MOST likely have?

arthritis

cystic fibrosis

heart disease

diabetes

cystic fibrosis

If the doctor says that Lydia's baby has a disorder caused by one single gene, the baby most likely has cystic fibrosis.

To determine what disorder Lydia's baby most likely has, we need to understand that genetic disorders caused by a single gene mutation can vary significantly. However, based on the given options, the disorder that is commonly caused by a single gene mutation is cystic fibrosis.

To understand more about individual genetic disorders, it's essential to consult with medical professionals, genetic testing, and utilize resources such as medical databases, scientific literature, and reputable websites dedicated to specific genetic disorders.