Genetic analysis of two cases with Dandy-Walker deformed fetus

Objective To explore the genetic etiology of two fetuses with Dandy-Walker malformation using single nucleotide polymorphism microarray (SNP-array). Methods The fetuses and their parents were subjected to G banding karyotype analysis. The fetuses were also subjected to SNP-array analysis. Results The parents of both fetuses showed a normal karyotype. One fetus has a 46, X, ? i(X)(q10), while for another conventional cell culture has failed. SNP-array showed that one fetus carried a 6p25.3p25.2 microdeletion, and another carried a Xp22.33p22.2 deletion and a Yq11.221q11 duplication. The abnormal fragments have involved FOXC1, SHOX and STS genes, which are associated with Dandy-Walker malformation. Conclusion Alteration of 6p25.3p25.2, Xp22.33p22.2 copy numbers probably underlies the Dandy-Walker syndrome in the fetuses. The disorder may be attributed to abnormal expression of FOXC1, SHOX, and STS genes. SNP-array can provide an important supplement for prenatal diagnosis. Key words: Dandy-Walker syndrome; Chromosome; Single nucleotide polymorphism microarray; Prenatal diagnosis