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Non-invasive prenatal testing (NIPT) using cell-free DNA can detect fetal chromosomal anomalies with high clinical sensitivity and specificity. In approximately 0.1% of clinical cases, the NIPT result and a subsequent diagnostic karyotype are discordant. Here we report a case of a 32-year-old pregnant patient with a 44.1 Mb duplication on the short arm of chromosome 4 detected by NIPT at 12 weeks’ gestation. Amniocentesis was carried out at 18 weeks’ gestation, followed by conventional and molecular cytogenetic analysis on cells from the amniotic fluid. SNP array analysis found a de novo deletion of 1.2 Mb at chromosome 4, and this deletion was found to be near the critical region of the Wolf-Hirschhorn syndrome. A normal 46,XY karyotype was identified by G-banding analysis. The patient underwent an elective termination and molecular investigations on tissues from the fetus, and the placenta confirmed the presence of type VI true fetal mosaicism. It is important that a patient receives counselling following a high-risk call on NIPT, with appropriate diagnostic analysis advised before any decisions regarding the pregnancy are taken. This case highlights the importance of genetic counselling following a high-risk call on NIPT, especially in light of the increasing capabilities of NIPT detection of sub-chromosomal deletions and duplications.

Objectives: To establish the positive predictive values (PPV) of cfDNA testing based on data from a nationwide survey of independent clinical cytogenetics laboratories. Methods: Prenatal diagnostic test results obtained by Italian laboratories between 2013 and March 2020 were compiled for women with positive non-invasive prenatal tests (NIPT), without an NIPT result, and cases where there was sex discordancy between the NIPT and ultrasound. PPV and other summary data were reviewed. Results: Diagnostic test results were collected for 1327 women with a positive NIPT. The highest PPVs were for Trisomy (T) 21 (624/671, 93%) and XYY (26/27, 96.3%), while rare autosomal trisomies (9/47, 19.1%) and recurrent microdeletions (8/55, 14.5%) had the lowest PPVs. PPVs for T21, T18, and T13 were significantly higher when diagnostic confirmation was carried out on chorionic villi (97.5%) compared to amniotic fluid (89.5%) (p < 0.001). In 19/139 (13.9%), of no result cases, a cytogenetic abnormality was detected. Follow-up genetic testing provided explanations for 3/6 cases with a fetal sex discordancy between NIPT and ultrasound. Conclusions: NIPT PPVs differ across the conditions screened and the tissues studied in diagnostic testing. This variability, issues associated with fetal sex discordancy, and no results, illustrate the importance of pre- and post-test counselling.

We report on a 9-year-old female patient with facial anomalies and developmental delay, heterozygous for three de novo rearrangements: a paracentric inversion of chromosome 7, an apparently balanced translocation between chromosome 1 and 7, involving the same inverted chromosome 7, detected by standard cytogenetic analysis [46,XX, der(7) inv(7)(q21.1q32.1)t(1;7)(q23q32.1)]; and a 2p16.1 deletion, spanning about 3.5 Mb of genomic DNA, shown by SNP-array analysis [arr 2p16.1 (56,706,666-60,234,485)x1 dn]. Clinical features and cytogenetic imbalance in our patient were similar to those reported in five published cases, suggesting that this genomic region is prone to recombination and its hemizygosity results in a distinct although variable spectrum of clinical manifestations.

Aicardi syndrome (AIS), a rare neurodevelopmental disorder thought to be caused by an X-linked dominant mutation, is characterized by 3 main features: agenesis of corpus callosum, infantile spams and chorioretinal lacunae. A genome-wide study of a girl with AIS lead us to identify a 6q deletion;12q duplication, derived from a maternal 6q;12q translocation. The two intellectually impaired brothers of the proband showed the same genomic anomalies, but not the constellation of features characterizing the AIS. This could be either a coincidental observation of 2 rare conditions, but can also suggest an alternative hypothesis for the genetic etiology of AIS, indicating the existence of a subset of autosomal genes whose mutation could act in a sex-confined manner.

The expression of fragile sites induced by aphidicolin (APC) was evaluated on metaphase chromosomes obtained from the peripheral blood lymphocytes of 26 women with breast cancer and 15 sex- and age-metched normal controls. Both the proportion of damaged cells (P

The recent identification of a common etiology among MASA syndrome (McKusick 303300), X-linked hydrocephalus (HSAS) (McKusick 307000) and other related neurological disorders, which had previously been considered distinct nosological entities, allowed us to diagnose MASA syndrome in a male fetus in a primigravida at the 29th week of gestation by sonographic signs of the MASA spectrum such as hydrocephalus and hypoplasia of corpus callosum. Indeed, the evidence of an X-linked neurological disease in the brother and the maternal uncle of the pregnant women enabled us to estimate a 25% risk of a male fetus being an affected hemizygote. The way in which a prenatal diagnosis, based on instrumental procedures, was reached is described since the authors were unable to perform, at the time of the observation, a molecular confirmation which was carried out only after birth. Copyright (C) 2000 John Wiley & Sons, Ltd.

A 36-year-old patient with a disorder characterized by severe mental retardation, behavioral problems, dysmorphic face, "muscular build," and hand/foot anomalies, is reported. Following a diagnosis of de novo pericentric inversion of chromosome 8 based on standard cytogenetic analysis, a subsequent 75 kb array-CGH investigation disclosed a deletion spanning for about 13.7 Mb in the 2q31.2q32.3 region. Whole painting of chromosome 8 established the intrachromosomal nature of the rearrangement and FISH analysis with locus-specific probes confirmed the deletion on the long arm of chromosome 2. The deleted region, clinical outcome, and medical history in this patient are mainly superimposable to those reported in a published 8-year-old boy, suggesting that this genomic segment is prone to rearrangements and its hemizygosity gives rise to a clinically recognizable syndrome. The role of some genes mapping in the deleted region and related with distinct disorders is discussed. Interestingly, deletion of MSTN gene, a negative regulator of muscle growth, was associated in our patient with a "muscular build," a feature which could be regarded as a handle for clinical recognition of this syndrome.

Introduction Progressive improvement has been observed in CKR and survival of CML patients (pts) in response to interferon (IFN)a-based regimens, or imatinib. The purpose of this study is the evaluation of: rate of, time to and duration of CKR in accordance to first line therapy employed and Sokal score; impact on overall survival of CKR, and Sokal score, separately considered or combined together. Patients. 109Ph’+ and 5Ph’−, (BCR-ABL positive), CML pts were treated at diagnosis with allogeneic transplantation (3 pts), hydroxyurea (HU) (19 pts), INFa (51pts, G1), INFa associated with ARA-C (20 pts, G2), imatinib alone (18 pts, G3), or imatinib combined with INFa (3 pts, G4). INFa was employed as second line therapy in 12 pts initially treated with hydroxyurea (G5), while INFa/ARA-C combination or imatinib alone was given to 24 (G6) and 23 (G7) pts with de novo or acquired resistance or intolerance to INFa. Third line therapy, consisting of the combination of imatinib with IFNa, was employed in 11 (G8) pts with no CKR (5 pts) or in complete cytogenetic, but not in molecular remission (6 pts). Results. 40 of 94 Ph’+ evaluable non-allotransplanted pts obtained one or more (overall 47) CKRs to INFa-based regimens or imatinib. CKR rate, median time to CKR and response duration are shown in table 1. In the analysis according to Sokal score 82/94 pts, with complete prognostic data at diagnosis, were included. The percentage of responders was higher in the low compared to the non-low Sokal risk group (57% vs. 31%). Irrespective of the treatment, median duration value of the first CKR was also better in the former [18+mths(1–64)] than in the latter group [6mths(2–54)] with 16 vs.4 pts still in first or subsequent remission. Overall survival for CKRs was 68+mths(5–275) vs. 52mths(5–270) for CKRs with 35 vs. 6 pts still alive respectively. Overall survival according to Sokal score at diagnosis was 61+ mths(5–275) for low vs 53mths(5–212) for non-low risk patients. The impact on survival of CKR and Sokal risk were then analyzed simultaneously. The median survival of 27 CKRs and 20 not CKRs with low Sokal risk were 61+mths(5–275)and 63 mths(14–270) respectively as compared to 73+mths(11–212) of 11 CKRs and 36mths(5–139) of 24 not CKRs with unfavourable characteristics at diagnosis. The number of patients still alive in these 4 groups were 24/27, 3/20, 8/11, 3/24 respectively at the time when this analysis was performed. Conclusions. The present data not only confirm the effectiveness of imatinib-over the INFa-based regimens in inducing CKR, but also suggest that response to treatment may be better than Sokal risk in predicting patient survival. Rate,time to and duration of CKR according to treatment PT Group CKR rate(%) time to CKR( months) Duration of CKR (months) N° of pts in cCKR Median Range Median Range G1 17 16 (3–28) 6 (2–53) 0 G2 30 11 (3–24) 15,5 (2–33) 0 G3 85 6 (2–14) 10+ (1–44) 11 G4 100 4 (4–5) 48 (2–50) 1 G5 0 0 G6 9 9,5 (7–12) 40,5 (17–64) 1 G7 54 9 (4–38) 21,5+ (3–54) 6 G8 80 3 (2–4) 26+ (4–48) 9

Two patients with M2 subtype of acute nonlymphocytic leukemia (ANLL) and trisomy 4 as a primary karyotype change are described. The abnormality was observed in 100% of bone marrow (BM) metaphases in both cases. It appeared alone in one case and was associated with trisomy 13 in 94% of metaphases in the other. These are the second and third cases of ANLL with trisomy 4 documented in Italy. Neither patient appears to have incurred any environmental or therapeutic insult.