[Prenatal diagnosis of two fetuses with chromosome 1p36 deletion syndrome]

To analyze two fetuses with multiple malformations revealed by ultrasonography using single nucleotide polymorphism array (SNP array), and to explore the strategy for the prenatal diagnosis of 1p36 deletion syndrome.

Amniocentesis was performed on the two pregnant women. Amnion fluid cells were cultured, and karyotypes of the fetuses were determined through G-banding analysis. Whole genome SNP array was used to detect genomic anomalies of the two fetuses. The karyotypes of their parents were determined through G-banding analysis of peripheral venous blood samples.

G-banding analysis showed a 46,XY,add(1p36)? and a 46,XX,add(1p36)? karyotype for fetuses 1 and 2, respectively. SNP array analysis showed that the fetus 1 had arr[19]1p36.33p36.32 (752 566 - 3 393 462)×1 and 7q35q36.3 (144 480 549 - 159 119 486)×3, and fetus 2 had arr[19]1p36.33p36.23 (752 566 - 8 362 754)×1, 6p25.3p22.3 (204 909 - 20 182 185)×3. The mother of fetus 1 had a 46,XX,t(1;7)(p36;q35) karyotype, and the mother of fetus 2 had a 46,XX,t(1;6)(p36;p22) karyotype. The karyotypes of both fathers appeared to be normal.

SNP array has the advantages such as high sensitivity and high accuracy for prenatal diagnosis, and can provide more detailed information for genetic counseling of 1p36 deletion syndrome.