Prenatal Diagnosis of Hemoglobinopathies

Prenatal diagnosis of severe genetic disorders, such as Down's syndrome and Tay-Sachs disease, has helped many couples at high risk of conceiving a defective child to have normal children. These diagnoses have depended upon ability to obtain amniotic fluid by mid-trimester amniocentesis and to grow in cell culture the sloughed fetal cells contained therein. Since biochemical markers present in skin fibroblasts are present in fetal amniotic cells, diseases with biochemical defects expressed in skin cells are amenable to diagnosis. No such procedure is possible with the hemoglobins. To study hemoglobin gene expression, one needs erythroid cells; other somatic cells will.