A 28 year old women suffering form sickle cell anaemia marries a 31 year old with no abnormality. What are the respective probabilities to have (i) sickle cell disease and (ii) sickle cell trait in their offspring?

Robbins basic pathology 9th edition page no 411,412 Answer is option 1, 0%and100%. Since mother is suffering from sickle cell anemia her gamete contains sickle cell trait, but as the father's gamete is fre of sickle cell trait there is no chance of offspring suffering from the disease but there is 100% of chance of offspring being sickle cell trait.