To evaluate the diagnostic value of single-nucleotide polymorphism (SNP) array testing in 1033 fetuses with ultrasound anomalies we investigated the prevalence and genetic nature of pathogenic findings. We reclassified all pathogenic findings into three categories: causative findings; unexpected diagnoses (UD); and susceptibility loci (SL) for neurodevelopmental disorders. After exclusion of trisomy 13, 18, 21, sex-chromosomal aneuploidy and triploidies, in 76/1033 (7.4%) fetuses a pathogenic chromosome abnormality was detected by genomic SNP array: in 19/1033 cases (1.8%) a microscopically detectable abnormality was found and in 57/1033 (5.5%) fetuses a pathogenic submicroscopic chromosome abnormality was detected. 58% (n=44) of all these pathogenic chromosome abnormalities involved a causative finding, 35% (n=27) a SL for neurodevelopmental disorder, and 6% (n=5) a UD of an early-onset untreatable disease. In 0.3% of parental samples an incidental pathogenic finding was encountered. Our results confirm that a genomic array should be the preferred first-tier technique in fetuses with ultrasound anomalies. All UDs involved early-onset diseases, which is beneficial for the patients to know. It also seems that UDs occur at a comparable frequency among microscopic and submicroscopic pathogenic findings. SL were more often detected than in pregnancies without ultrasound anomalies.

Additional Metadata
Persistent URL dx.doi.org/10.1038/ejhg.2015.193, hdl.handle.net/1765/91885
Journal European Journal of Human Genetics
Citation
Srebniak, M.I, Diderich, K.E.M, Joosten, A-M.S, Govaerts, L.C, Knijnenburg, J, de Vries, F.A.T, … Van Opstal, A.R.M. (2016). Prenatal SNP array testing in 1000 fetuses with ultrasound anomalies: Causative, unexpected and susceptibility CNVs. European Journal of Human Genetics, 24(5), 645–651. doi:10.1038/ejhg.2015.193