Positive predictive values and outcomes for uninformative cell-free DNA tests: An Italian multicentric Cytogenetic and cytogenomic Audit of diagnOstic testing (ICARO study).

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.

Children and adults affected by Cri du Chat syndrome: Care's recommendations.

Our objective is to collect data and information for a better care and follow up in Cri du Chat patients. We conducted a literature review in August 2017 and then discuss the outcomes within the ABC (Associazione Bambini Cri du Chat, Italian CdC families support group). A proposal for clinical, laboratory and imaging work up should be performed at various ages in CdC patients.

Expanding the phenotype of reciprocal 1q21.1 deletions and duplications: a case series.

Background: Recurrent reciprocal 1q21.1 deletions and duplications have been associated with variable phenotypes. Phenotypic features described in association with 1q21.

Concentration-dependent metabolic effects of metformin in healthy and Fanconi anemia lymphoblast cells.

Metformin (MET) is the drug of choice for patients with type 2 diabetes and has been proposed for use in cancer therapy and for treating other metabolic diseases. More than 14,000 studies have been published addressing the cellular mechanisms affected by MET. However, several in vitro studies have used concentrations of the drug 10-100-fold higher than the plasmatic concentration measured in patients.

Brachydactyly type E in an Italian family with 6p25 trisomy.

Brachydactyly type E is a congenital limb malformation characterized by small hands and feet as a result of shortened metacarpals and metatarsals. Genetic causes of this anomaly are heterogeneous and only partially characterized. In this report we describe an Italian family in which four subjects share brachydactyly type E and a 3 Mb microduplication in region 6p25.

Microdeletion 2q23.3q24.1: exploring genotype-phenotype correlations.

We report a case of a 13-year-old girl with a 5.4 Mb de novo deletion, encompassing bands 2q23.3q24.

Molecular analysis of Fanconi anemia: the experience of the Bone Marrow Failure Study Group of the Italian Association of Pediatric Onco-Hematology.

Fanconi anemia is an inherited disease characterized by congenital malformations, pancytopenia, cancer predisposition, and sensitivity to cross-linking agents. The molecular diagnosis of Fanconi anemia is relatively complex for several aspects including genetic heterogeneity with mutations in at least 16 different genes. In this paper, we report the mutations identified in 100 unrelated probands enrolled into the National Network of the Italian Association of Pediatric Hematoly and Oncology.

14q13.1-21.1 deletion encompassing the HPE8 locus in an adolescent with intellectual disability and bilateral microphthalmia, but without holoprosencephaly.

Interstitial deletions involving 14q13.1q21.1 are rare.

Characterization of a complex rearrangement involving chromosomes 1, 4 and 8 by FISH and array-CGH.

Complex chromosomal rearrangements (CCRs) are structural aberrations involving more than two chromosomes with at least three breakpoints. CCRs can be divided into familial and de novo. Balanced CCR are extremely rare in humans and are at high risk of producing unbalanced gametes.

Interstitial deletion of chromosome 2p15-16.1: report of two patients and critical review of current genotype-phenotype correlation.

Unlabelled: We report two individuals with developmental delay and dysmorphic features, in whom array-based comparative genomic hybridization (array CGH) led to the identification of a 2p15p16.1 de novo deletion. In the first patient (Patient 1) a familial deletion of 6q12, inherited from her father, was also detected.

Clinical significance of rare copy number variations in epilepsy: a case-control survey using microarray-based comparative genomic hybridization.

Objective: To perform an extensive search for genomic rearrangements by microarray-based comparative genomic hybridization in patients with epilepsy.

Design: Prospective cohort study.

Setting: Epilepsy centers in Italy.

The first case of myoclonic epilepsy in a child with a de novo 22q11.2 microduplication.

Chromosome 22, particularly the q11.2 sub-band, has long been recognized as responsible for multiple congenital anomaly disorders. In particular, its susceptibility to subtle microdeletions or, more rarely, microduplications has been attributed to the presence of several low-copy repeats spanning the region as mediators of nonallelic homologous recombination that result in 22q11.

A 12.4 Mb direct duplication in 19q12-q13 in a boy with cardiac and CNS malformations and developmental delay.

The interstitial duplication of the long arm of chromosome 19 is a rare abnormality, characterized by developmental delay and dysmorphic features, also reported in association with cardiac, urinary, and CNS malformations. We describe a new case of de novo 19q12-q13.2 duplication characterized by fluorescent in situ hybridization (FISH) and array comparative genomic hybridization (CGH) and, by reviewing the data from previous articles, we report a tentative genotype/phenotype correlation.

Clinical phenotype and molecular characterization of 6q terminal deletion syndrome: Five new cases.

Mental retardation, facial dysmorphisms, seizures, and brain abnormalities are features of 6q terminal deletions. We have ascertained five patients with 6q subtelomere deletions (four de novo, one as a result of an unbalanced translocation) and determined the size of the deletion ranging from 3 to 13 Mb. Our patients showed a recognizable phenotype including mental retardation, characteristic facial appearance, and a distinctive clinico-neuroradiological picture.

Cytogenetic and molecular evaluation of 241 small supernumerary marker chromosomes: cooperative study of 19 Italian laboratories.

Purpose: We evaluated the experiences of 19 Italian laboratories concerning 241 small supernumerary marker chromosomes (sSMCs) with the aim of answering questions arising from their origin from any chromosome, their variable size and genetic content, and their impact on the carrier's phenotype.

Methods: Conventional protocols were used to set up the cultures and chromosome preparations. Both commercial and homemade probes were used for the fluorescent in situ hybridization analyses.

Microarray transcript profiling distinguishes the transient from the acute type of megakaryoblastic leukaemia (M7) in Down's syndrome, revealing PRAME as a specific discriminating marker.

Transient myeloproliferative disorder (TMD) is a unique, spontaneously regressing neoplasia specific to Down's syndrome (DS), affecting up to 10% of DS neonates. In 20-30% of cases, it reoccurs as progressive acute megakaryoblastic leukaemia (AMKL) at 2-4 years of age. The TMD and AMKL blasts are morphologically and immuno-phenotypically identical, and have the same acquired mutations in GATA1.

Acquired mutations in GATA1 in neonates with Down's syndrome with transient myeloid disorder.

Transient myeloid disorder is a unique self-regressing neoplasia specific to Down's syndrome. The transcription factor GATA1 is needed for normal growth and maturation of erythroid cells and megakaryocytes. Mutations in GATA1 have been reported in acute megakaryoblastic leukaemia in Down's syndrome.

Mild generalized epilepsy and developmental disorder associated with large inv dup(15).

Purpose: Several studies attempted to clarify the genotype-phenotype correlations in patients with inverted duplication of chromosome 15 [inv dup(15)], which is usually characterized by severe mental retardation and epilepsy in individuals with large duplications including the Prader-Willi/Angelman region. We report two patients with inv dup(15) who, in spite of a large duplication, had a mild phenotype including adult-onset epilepsy. This report may help to define the milder spectrum of the syndrome.