TAY-SACHS DISEASE (TSD): PRENATAL DIAGNOSIS AND HETEROZYGOTE SCREENING

Abstract

From 1969 (when the metabolic error in TSD was defined) to August 1976, the births of 115 infants with TSD have been prevented. This derives from prenatal monitoring of 461 pregnancies at-risk for TSD in centers from 12 reporting countries. Three hundred & seventy-one pregnancies were in couples with 1 or more previously affected children and 90 in couples identified “at-risk” thru heterozygote screening. All fetal TSD diagnoses were confirmed, where aborted tissue was available (103/115); 1 affected infant was missed by prenatal study; 4 TSD-identified fetuses were not electively aborted; and 340 unaffected children were born as predicted.Sixty cities in 5 nations - - U.S., Canada, Israel, U.K., and S. Africa -- have initiated carrier screening programs. More than 150,000 adults have volunteered for the carrier detection serum Hex A test; over 6,000 heterozygotes identified; and 125 at-risk couples discovered (both parents: heterozygotes). An heterozygote frequency of 0.037 (1 in 27.3) is evident among the 101,000 American Jews screened (without known carriers or TSD infants in their families).A quality control study in 13 N. American serum testing centers indicates nearly perfect accuracy in TSD heterozygote detection. Personal interviews with identified carriers suggest little, if any, psychological stigmatization. It is suggested from this experience that this approach to the control of TSD may serve as a model for future recessive genetic disease prevention efforts.