ABSTRACT
[ ABSTRACT] AIM:To evaluate the clinical application of single nucleotide polymorphism array ( SNP array) in prenatal diagnosis for screening the abnormality of women with Down’ s syndrome ( DS) .METHODS:The amniotic fluid samples ( n=312) collected by amniocentesis for the DS screening abnormality women were tested by karyotyping and SNP array analysis, respectively.The findings of karyotyping and SNP array analysis were compared.RESULTS:Two cases of trisomy 21 were identified by karyotyping and SNP array analysis, but SNP array analysis failed to identify 6 cases of chro-mosome balanced structural rearrangement.SNP detected 176 cases copy number variants ( CNVs) in 303 cases normal karyotype were detected by SNP, including 106 benign CNVs, 61 variants of unknown significance (VOUS), 9 de novo CNVs, and none of them was pathogenic.The distribution difference of CNVs in DS screening positive group and DS screening positive plus advanced maternal age group was not statistically significant ( P>0.05) .Furthermore, we reported 14 kinds of CNVs for the first time in population.CONCLUSION:SNP array can further assure chromosome microdupli-cation/microdeletion.In normal karyotype fetus of prenatal diagnosis, SNP can detect some clinical significant CNVs.