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This report describes a newborn girl presenting with some of the common features of DiGeorge syndrome/velocardiofacial syndrome (DGS/VCFS), including hypocalcemia, atrial septal defect, and aortic stenosis. Several genetic tests were carried out to determine the origin of the clinical phenotype. MLPA was initially performed followed by aCGH, cytogenetic analysis, and FISH. Cytogenetic analysis of the proband's parents was also done. MLPA revealed a deletion in 22q11.1q11.2 spanning from the cat eye syndrome region to the most commonly deleted region in DGS/VCFS patients. The size of the deletion as defined by aCGH was 3.2 Mb. The karyotype of the proband was 45,XX,der(1)t(1;22)(p36.3;q11.2)dn,-22, the karyotypes of the parents were normal. FISH analysis showed that the 22q11 deletion occurred in the der(1). No loss or gain of chromosomal material was evident for chromosome 1, as confirmed by MLPA, aCGH, and FISH. Unbalanced translocations resulting in DGS are relatively rare, with limited reports in the literature. To our knowledge, this is the second case involving chromosome 1 and the first one with breakpoints in 1p36 and 22q11.2. This case also emphasizes the importance of combining diagnostic methods to better understand a given genetic abnormality.

Introduction Non-Invasive Prenatal Testing (NIPT) for fetal aneuploidies using cell-free DNA (cfDNA) has been widely adopted in clinical practice due to its improved accuracy. A number of NIPT tests have been developed and validated. The purpose of this study is to evaluate the performance of the Veracity NIPT test for sex chromosome aneuploidy (SCA) detection in singleton pregnancies, autosomal aneuploidy detection in twin pregnancies and evaluation of Veracity clinical performance under routine NIPT conditions in a diverse cohort. Methods Blinded retrospective study in singleton pregnancies (n = 305); blinded retrospective and prospective study in twin pregnancies (n = 306) and prospective evaluation of clinical performance in singleton and twin pregnancies (n = 10564). Results Validation study results for the detection of SCAs in singleton pregnancies exhibited 100% sensitivity and specificity and correctly classified 7 (45,X), 4 (47,XXY), 2 (47,XXX) and 1 (47,XYY) cases. Validation study results for autosomal aneuploidy detection in twin pregnancies exhibited 100% sensitivity and specificity and correctly classified 3 trisomy 21, 1 trisomy 18 and 1 trisomy 13 samples. Clinical performance evaluation of Veracity was performed in 10564 pregnancies with median gestational age of 13 weeks, median maternal age 35 years and median gestational weight of 64 kg. Based on confirmation feedback the PPV for trisomies 21, 18 and 13 was estimated at 100% (95% CI, 92–100%), 100% (95% CI, 69–100%) and 71% (95% CI, 29–96%), respectively. Estimated PPV for Monosomy X was 57% (95%CI, 18–90%), while the NPV for SCA detection was estimated at 100% (95% CI, 99.94–100%). Conclusion Veracity NIPT test is based on a very powerful, highly accurate methodology that can be safely applied in the clinical setting. Electronic supplementary material The online version of this article (10.1186/s13039-019-0446-0) contains supplementary material, which is available to authorized users.