OBJECTIVE: Evaluation of results in a consecutive series of 29 prenatal diagnoses for the Cockayne syndrome. METHODS: Recovery of DNA-synthesis in UV-irradiated cultured fetal cells was measured by scintillation counting of incorporated (3)H-thymidine. Semiquantitative autoradiographic assessment of the recovery of RNA-synthesis (RecRS) was used as an adjunctive method. RESULTS: In 26 of the 29 pregnancies at risk, a definite diagnosis was directly made, based on normal (n = 23) or clearly reduced (n = 3) recovery of DNA-synthesis in UV-irradiated cultured chorionic villus (CV) cells (n = 23) or amniocytes (n = 3). Adjunctive studies were performed in several pregnancies to corroborate the initial results. On three occasions initial results were unreliable, which required investigation of the recovery of RNA-synthesis (n = 2) or even additional amniocentesis (n = 1) to achieve a firm diagnosis. Thus, four affected fetuses were diagnosed in 29 pregnancies at risk (13.8%). CONCLUSION: Reliable prenatal diagnosis of the Cockayne syndrome can be made by the demonstration of a strongly reduced recovery of DNA-synthesis in UV-irradiated cultured chorionic villus cells or amniocytes. Assessment of the recovery of RNA-synthesis was needed as an adjunctive method in rare cases of poor cell growth and DNA-synthesis.
OBJECTIVE: Evaluation of results in a consecutive series of 29 prenatal diagnoses for the Cockayne syndrome. METHODS: Recovery of DNA-synthesis in UV-irradiated cultured fetal cells was measured by scintillation counting of incorporated (3)H-thymidine. Semiquantitative autoradiographic assessment of the recovery of RNA-synthesis (RecRS) was used as an adjunctive method. RESULTS: In 26 of the 29 pregnancies at risk, a definite diagnosis was directly made, based on normal (n = 23) or clearly reduced (n = 3) recovery of DNA-synthesis in UV-irradiated cultured chorionic villus (CV) cells (n = 23) or amniocytes (n = 3). Adjunctive studies were performed in several pregnancies to corroborate the initial results. On three occasions initial results were unreliable, which required investigation of the recovery of RNA-synthesis (n = 2) or even additional amniocentesis (n = 1) to achieve a firm diagnosis. Thus, four affected fetuses were diagnosed in 29 pregnancies at risk (13.8%). CONCLUSION: Reliable prenatal diagnosis of the Cockayne syndrome can be made by the demonstration of a strongly reduced recovery of DNA-synthesis in UV-irradiated cultured chorionic villus cells or amniocytes. Assessment of the recovery of RNA-synthesis was needed as an adjunctive method in rare cases of poor cell growth and DNA-synthesis.