When sickle cell carrier marries a normal woman, the probability of them having a normal offspring is

When a person has sickle cell trait (i.e., is a carrier), it means they have one copy of the sickle cell gene and one copy of the normal gene. If a person with sickle cell trait marries a normal woman who has two copies of the normal gene, their offspring have a 50% chance of inheriting the sickle cell gene from the carrier parent and a 50% chance of inheriting the normal gene from the normal parent. Therefore, the probability of the offspring being a carrier of sickle cell trait (i.e., having one copy of the sickle cell gene and one copy of the normal gene) is 50%. The probability of the offspring having two copies of the normal gene and not having sickle cell trait is also 50%. It's worth noting that if both parents have sickle cell trait, their offspring have a 25% chance of inheriting two copies of the sickle cell gene and having sickle cell disease, a 50% chance of inheriting one copy of the sickle cell gene and being a carrier, and a 25% chance of inheriting two copies of the normal gene and not having sickle cell trait or disease.