[Genetic diagnosis and follow up of a fetus with Emanuel syndrome].

OBJECTIVE

To carry out genetic analysis for a fetus with Dandy-Walker malformation and provide prenatal diagnosis for its parents during the subsequent pregnancy.

METHODS

Routine G-banding was carried out to analyze the karyotype of the fetus and its parents, and next-generation sequencing (NGS) and fluorescence in situ hybridization (FISH) were used to verify the result.

RESULTS

The father showed a normal karyotype, while the mother was found to carry a balanced t(11; 22) (q23; q11) translocation. NGS and FISH analysis verified that the supernumerary marker chromosome carried by the fetus was der(22) t(11; 22) (q23;q11). The fetus was diagnosed with Emanuel syndrome. During the next pregnancy, the fetus was found to carry the same balanced translocation as its mother. After genetic counseling, the couple decided to continue with the pregnancy, and eventually delivered a healthy baby.

CONCLUSION

A fetal case of Emanuel syndrome has been identified. The derivative der(22) t(11; 22)(q23; q11) chromosome probably underlies the Dandy-Walker malformation in the fetus. Combined cytogenetic and molecular analyses can attain a more precise diagnosis for fetal abnormalities detected by ultrasonography.