Chorionic villous sampling is done in all except
Chorionic villi are extremely good source of fetal DNA and thus ideal for PCR and DNA analysis to diagnose single gene defects like hemoglobinopathies,cysticfibrosis,duchenne muscular dystrophy.Represents confined placental mosaicism.It can be used to diagnose storage diseases like Tay Sachs and Gaucher&;s disease. TEXTBOOK OF OBSTETRICS,SHEILA BALAKRISHNAN,Pg no:503,2nd edition
Phenylketonuria
Down's syndrome
Neural tube defect
Thalassemia/sickle cell anemia
Diagnosis in obstetrics