Identification and characterization of novel ETV4 splice variants in prostate cancer.

ETV4, one of ETS proteins overexpressed in prostate cancer, promotes migration, invasion, and proliferation in prostate cells. This study identifies a series of previously unknown ETV4 alternatively spliced transcripts in human prostate cell lines. Their expression has been validated using several unbiased techniques, including Nanopore sequencing. Most of these transcripts originate from an in-frame exon skipping and, thus, are expected to be translated into ETV4 protein isoforms. Functional analysis of the most abundant among these isoforms shows that they still bear an activity, namely a reduced ability to promote proliferation and a residual ability to regulate the transcription of ETV4 target genes. Alternatively spliced genes are common in cancer cells: an analysis of the TCGA dataset confirms the abundance of these novel ETV4 transcripts in prostate tumors, in contrast to peritumoral tissues. Since none of their translated isoforms have acquired a higher oncogenic potential, such abundance is likely to reflect the tumor deranged splicing machinery. However, it is also possible that their interaction with the canonical variants may contribute to the biology and the clinics of prostate cancer. Further investigations are needed to elucidate the biological role of these ETV4 transcripts and of their putative isoforms.

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. 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.

Validation of a method for noninvasive prenatal testing for fetal aneuploidies risk and considerations for its introduction in the Public Health System.

OBJECTIVE: The aim of this study was to validate noninvasive prenatal testing (NIPT) for fetal aneuploidies by whole-genome massively parallel sequencing (MPS). METHODS: MPS was performed on cell-free DNA (cfDNA) isolated from maternal plasma in two groups: a first set of 186 euploid samples and a second set of 195 samples enriched of aneuploid cases (n = 69); digital PCR for fetal fraction (FF) assessment was performed on 178/381 samples. Cases with <10 × 106 reads (n = 54) were excluded for downstream data analysis. Follow-up data (invasive testing results or neonatal information) were available for all samples. Performances in terms of specificity/sensitivity and Z-score distributions were evaluated. RESULTS: All positive samples for trisomy 21 (T21) (n = 43), trisomy 18 (T18) (n = 6) and trisomy 13 (T13) (n = 7) were correctly identified (sensitivity: 99.9%); 5 false positive results were reported: 3 for T21 (specificity = 98.9%) and 2 for T13 (specificity = 99.4%). Besides FF, total cfDNA concentration seems another important parameter for MPS, since it influences the number of reads. CONCLUSIONS: The overall test accuracy allowed us introducing NIPT for T21, T18 and T13 as a clinical service for pregnant women after 10 + 4 weeks of gestation. Sex chromosome aneuploidy assessment needs further validation due to the limited number of aneuploid cases in this study.

Thin and thick primary cutaneous melanomas reveal distinct patterns of somatic copy number alterations.

Cutaneous melanoma is one of the most aggressive type of skin tumor. Early stage melanoma can be often cured by surgery; therefore current management guidelines dictate a different approach for thin (<1mm) versus thick (>4mm) melanomas. We have carried out whole-exome sequencing in 5 thin and 5 thick fresh-frozen primary cutaneous melanomas. Unsupervised hierarchical clustering analysis of somatic copy number alterations (SCNAs) identified two groups corresponding to thin and thick melanomas. The most striking difference between them was the much greater abundance of SCNAs in thick melanomas, whereas mutation frequency did not significantly change between the two groups. We found novel mutations and focal SCNAs in genes that are embryonic regulators of axon guidance, predominantly in thick melanomas. Analysis of publicly available microarray datasets provided further support for a potential role of Ephrin receptors in melanoma progression. In addition, we have identified a set of SCNAs, including amplification of BRAF and ofthe epigenetic modifier EZH2, that are specific for the group of thick melanomas that developed metastasis during the follow-up. Our data suggest that mutations occur early during melanoma development, whereas SCNAs might be involved in melanoma progression.

Molecular Dissection Using Array Comparative Genomic Hybridization and Clinical Evaluation of An Infertile Male Carrier of An Unbalanced Y;21 Translocation: A Case Report and Review of The Literature.

Chromosomal defects are relatively frequent in infertile men however, translocations between the Y chromosome and autosomes are rare and less than 40 cases of Y-autosome translocation have been reported. In particular, only three individuals has been described with a Y;21 translocation, up to now. We report on an additional case of an infertile man in whom a Y;21 translocation was associated with the deletion of a large part of the Y chromosome long arm. Applying various techniques, including conventional cytogenetic procedures, fluorescence in situ hybridisation (FISH) analysis and array comparative genomic hybridization (array-CGH) studies, we identified a derivative chromosome originating from a fragment of the short arm of the chromosome Y translocated on the short arm of the 21 chromosome. The Y chromosome structural rearrangement resulted in the intactness of the entire short arm, including the sex-determining region Y (SRY) and the short stature homeobox (SHOX) loci, although translocated on the 21 chromosome, and the loss of a large part of the long arm of the Y chromosome, including azoospermia factor-a (AZFa), AZFb, AZFc and Yq heterochromatin regions. This is the first case in which a (Yp;21p) translocation has been ascertained using an array-CGH approach, thus reporting details of such a rearrangement at higher resolution.

16p11.2 de novo microdeletion encompassing SRCAP gene in a patient with speech impairment, global developmental delay and behavioural problems.

We describe a patient with speech impairment, global developmental delay, behavioural problems and a 186 kb de novo microdeletion on 16p11.2. There are four OMIM Phenotypes entries partially overlapping with the deleted region and related to recurrent microdeletions/microduplications in 16p11.2. A detailed review of published data shows that microdeletions/microduplications' boundaries do not include genes that are deleted in the case here reported. The deletion encompasses 9 RefSeq genes and includes SRCAP (Snf2-related CREBBP activator protein, OMIM*611421), a disease causing gene. Recently, truncating mutations in the SRCAP gene have been shown to cause Floating-Harbor syndrome (FHS, OMIM#136140), a rare disorder characterized by peculiar facial features, short stature with delayed osseous maturation and speech impairment. The patient reported here shows few subtle phenotypic features resembling that of FHS, but she does not have sufficient signs and symptoms for the clinical diagnosis and a clinical classification based on facial gestalt is not possible. This is the first report of a 16p11.2 deletion completely removing one copy of SRCAP, suggesting that haploinsufficiency of this gene could be associated to speech impairment, global developmental delay, behavioural problems and few subtle phenotypic features resembling FHS. However, further evidence for the putative causative role of SRCAP isolated deletion is needed.

Novel α-actinin 2 variant associated with familial hypertrophic cardiomyopathy and juvenile atrial arrhythmias: a massively parallel sequencing study.

BACKGROUND: Next-generation sequencing might be particularly advantageous in genetically heterogeneous conditions, such as hypertrophic cardiomyopathy (HCM), in which a considerable proportion of patients remain undiagnosed after Sanger. In this study, we present an Italian family with atypical HCM in which a novel disease-causing variant in α-actinin 2 (ACTN2) was identified by next-generation sequencing. METHODS AND RESULTS: A large family spanning 4 generations was examined, exhibiting an autosomal dominant cardiomyopathic trait comprising a variable spectrum of (1) midapical HCM with restrictive evolution with marked biatrial dilatation, (2) early-onset atrial fibrillation and atrioventricular block, and (3) left ventricular noncompaction. In the proband, 48 disease genes for HCM, selected on the basis of published reports, were analyzed by targeted resequencing with a customized enrichment system. After bioinformatics analysis, 4 likely pathogenic variants were identified: TTN c.21977G>A (p.Arg7326Gln); TTN c.8749A>C (p.Thr2917Pro); ACTN2 c.683T>C (p.Met228Thr); and OBSCN c.13475T>G (p.Leu4492Arg). The novel variant ACTN2 c.683T>C (p.Met228Thr), located in the actin-binding domain, proved to be the only mutation fully cosegregating with the cardiomyopathic trait in 18 additional family members (of whom 11 clinically affected). ACTN2 c.683T>C (p.Met228Thr) was absent in 570 alleles of healthy controls and in 1000 Genomes Project and was labeled as Damaging by in silico analysis using polymorphism phenotyping v2, as Deleterious by sorts intolerant from tolerant, and as Disease-Causing by Mutation Taster. CONCLUSIONS: A targeted next-generation sequencing approach allowed the identification of a novel ACTN2 variant associated with midapical HCM and juvenile onset of atrial fibrillation, emphasizing the potential of such approach in HCM diagnostic screening.

Discovering chimeric transcripts in paired-end RNA-seq data by using EricScript.

MOTIVATION: The discovery of novel gene fusions can lead to a better comprehension of cancer progression and development. The emergence of deep sequencing of trancriptome, known as RNA-seq, has opened many opportunities for the identification of this class of genomic alterations, leading to the discovery of novel chimeric transcripts in melanomas, breast cancers and lymphomas. Nowadays, few computational approaches have been developed for the detection of chimeric transcripts. Although all of these computational methods show good sensitivity, much work remains to reduce the huge number of false-positive calls that arises from this analysis. RESULTS: We proposed a novel computational framework, named chimEric tranScript detection algorithm (EricScript), for the identification of gene fusion products in paired-end RNA-seq data. Our simulation study on synthetic data demonstrates that EricScript enables to achieve higher sensitivity and specificity than existing methods with noticeably lower running times. We also applied our method to publicly available RNA-seq tumour datasets, and we showed its capability in rediscovering known gene fusions.

372 kb microdeletion in 18q12.3 causing SETBP1 haploinsufficiency associated with mild mental retardation and expressive speech impairment.

Several cases of interstitial deletion encompassing band 18q12.3 are described in patients with mild dysmorphic features, mental retardation and impairment of expressive language. The critical deleted region contains SETBP1 gene (SET binding protein 1). Missense heterozygous mutations in this gene cause Schinzel-Giedion syndrome (SGS, MIM#269150), characterized by profound mental retardation and multiple congenital malformations. Recently, a 18q12.3 microdeletion causing SETBP1 haploinsufficiency has been described in two patients that show expressive speech impairment, moderate developmental delay and peculiar facial features. The phenotype of individual with partial chromosome 18q deletions does not resemble SGS. The deletion defines a critical region in which SETBP1 is the major candidate gene for expressive speech defect. We describe an additional patient with the smallest 18q12.3 microdeletion never reported that causes the disruption of SETBP1. The patient shows mild mental retardation and expressive speech impairment with striking discrepancy between expressive and receptive language skills. He is able to communicate using gestures and mimic expression of face and body with surprising efficacy. The significant phenotypic overlap between this patient and the cases previously reported enforce the hypothesis that SETBP1 haploinsufficiency may have a role in expressive language development.

Association between primary open-angle glaucoma (POAG) and WDR36 sequence variance in Italian families affected by POAG.

BACKGROUND/AIMS: To assess the involvement of WDR36 sequence variance in primary open-angle glaucoma (POAG) in Italian patients. METHODS: A cohort of 34 Italian families affected by POAG was analysed by denaturing high-performance liquid chromatography for mutation in the WDR36 gene. Among the 34 families enrolled, 25 were affected by high-tension glaucoma (HTG), four by juvenile open-angle glaucoma and one by normal tension glaucoma. In addition, four families presented both juvenile open-angle glaucoma and HTG-POAG patients within the same pedigree. RESULTS: Four previously identified intronic polymorphisms (IVS5+30C→T; IVS12+90 G→T; IVS13+89G→A; IVS16-30A→G) and a novel one (IVS21-75G→A) have been identified. In addition, one proband was found to carry the p.D658G mutation reported as the more recurrent disease-causing allele. CONCLUSIONS: The findings suggest that WDR36 sequence variance is only a rare cause of glaucoma in Italian families. Clearly, investigation of additional families with extensive studies is needed to clarify the role of WDR36 in the pathophysiology of glaucoma.

Easy genotyping of complement C3 'slow' and 'fast' allotypes by tetra-primer amplification refractory mutation system PCR.

Complement C3 'slow' and 'fast' allotypes are associated with immune-mediated disorders and may affect the outcome of renal transplantation. We report a tetra-primer amplification refractory mutation system PCR (T-ARMS-PCR) that provides a rapid, reproducible and cost-effective method to genotype both complement C3 'slow' and 'fast' alleles by a single tube reaction.

Erratum to: Clinical and molecular characterization of Italian patients affected by Cohen syndrome.

The complete affiliations of two authors appeared incorrectly. The affiliations of A. Selicorni and D. Milani should be given as.

Clinical and molecular characterization of Italian patients affected by Cohen syndrome.

Cohen syndrome is an autosomal recessive disorder with variability in the clinical manifestations, characterized by developmental delay, visual disability, facial dysmorphisms and intermittent neutropenia. We described a cohort of 10 patients affected by Cohen syndrome from nine Italian families ranging from 5 to 52 years at assessment. Characteristic age related facial changes were well documented. Visual anomalies, namely retinopathy and myopia, were present in 9/10 patients (retinopathy in 9/10 and myopia in 8/10). Truncal obesity has been described in all patients older than 6 years (8/8). DNA samples from all patients were analyzed for mutations in COH1 by DHPLC. We detected 15 COH1 alterations most of them were truncating mutations, only one being a missense change. Partial gene deletions have been found in two families. Most mutations were private. Two were already reported in the literature just once. A single base deletion leading to p.T3708fs3769, never reported before, was found in three apparently unrelated families deriving from a restricted area of the Veneto's lowland, between Padova town and Tagliamento river, in heterozygous state. Given the geographical conformation of this region, which is neither geographically or culturally isolated, a recent origin of the mutation could be hypothesized.

Clinical and molecular characterization of a patient with a 2q31.2-32.3 deletion identified by array-CGH.

We report on a patient with a de novo interstitial deletion of the long arm of chromosome 2 involving bands 2q31.2-2q32.3. The patient shows severe mental retardation, absence of speech, sleep disturbances, behavioral problems, and some dysmorphic features. In particular, he presents with macrocephaly, high forehead, thick and coarse hair, thick eyebrows, synophrys, increased inner and outer canthal distance, bifid nasal tip, high palate, micrognathia, dysmorphic right ear, and long and tapering fingers. Array-CGH analysis allowed us to identify and characterize a 2q interstitial deletion of about 13 Mb, involving the segment between cytogenetic bands 2q31.2 and 2q32.3. The deletion was confirmed by quantitative PCR. We compare the phenotype of our patient with those already reported in literature. In particular, we discuss the similarities shared with two recently reported patients, studied by array-CGH, who show an overlapping deletion. The common clinical features are: long face, high forehead, abnormal teeth and ears, midface hypoplasia, high palate, micrognathia, transparent and thin skin, high frequency of inguinal hernia, severe development impairment, and behavioral problems. Some genes located in the deleted region may be good candidates for the neurological phenotype such as ZNF533 and MYO1B, which are both involved in neuronal function. Furthermore, the GLS gene could be a good candidate in generating the behavioral phenotype in the patient. In fact, it encodes for the major enzyme yielding glutamate from glutamine and it can be implicated in behavioral disturbances in which glutamate acts as a neurotransmitter.

Italian Rett database and biobank.

Rett syndrome is the second most common cause of severe mental retardation in females, with an incidence of approximately 1 out of 10,000 live female births. In addition to the classic form, a number of Rett variants have been described. MECP2 gene mutations are responsible for about 90% of classic cases and for a lower percentage of variant cases. Recently, CDKL5 mutations have been identified in the early onset seizures variant and other atypical Rett patients. While the high percentage of MECP2 mutations in classic patients supports the hypothesis of a single disease gene, the low frequency of mutated variant cases suggests genetic heterogeneity. Since 1998, we have performed clinical evaluation and molecular analysis of a large number of Italian Rett patients. The Italian Rett Syndrome (RTT) database has been developed to share data and samples of our RTT collection with the scientific community (http://www.biobank.unisi.it). This is the first RTT database that has been connected with a biobank. It allows the user to immediately visualize the list of available RTT samples and, using the "Search by" tool, to rapidly select those with specific clinical and molecular features. By contacting bank curators, users can request the samples of interest for their studies. This database encourages collaboration projects with clinicians and researchers from around the world and provides important resources that will help to better define the pathogenic mechanisms underlying Rett syndrome.

Optineurin gene is not involved in the common high-tension form of primary open-angle glaucoma.

PURPOSE: To assess the influence of optineurin in the more common high-tension, primary open-angle glaucoma (POAG). METHODS: Eighteen sporadic cases and 35 probands from 35 familial cases, including three families with one member having normal-tension glaucoma (NTG), were enrolled. Using transgenomic WAVE denaturing high-performance liquid chromatography (DHPLC), all coding portion of the optineurin gene (from exon 4 to exon 16) was analyzed. Samples displaying an altered elution profile were sequenced to confirm and identify sequence variants. Exon 4 containing the previously reported p.E50K (Glu50Lys) recurrent mutation (covering 13% of normotensive cases) was entirely sequenced. RESULTS: We did not detect the mutation p.E50K, and we did not find any other pathogenic mutation. A putative splice-site mutation was detected in one family. Extension of segregation analysis to additional family members and mRNA investigation failed to establish a certain involvement of this mutation with the disease. We detected a number of common polymorphisms, including the previously reported p.M98K (Met98Lys) variant. CONCLUSIONS: In this population, mutations in the optineurin gene are not associated with adult-onset primary POAG.

Autosomal recessive Alport syndrome: an in-depth clinical and molecular analysis of five families.

BACKGROUND: Alport syndrome (ATS) is a progressive inherited nephropathy characterized by irregular thinning, thickening and splitting of the glomerular basement membrane (GBM) often associated with hearing loss and ocular symptoms. ATS has been shown to be caused by COL4A5 mutations in its X-linked form and by COL4A3 and COL4A4 mutations in its autosomal forms. METHODS: Five families with a suspicion of ATS were investigated both from a clinical and molecular point of view. COL4A3 and COL4A4 genes were analysed by DHPLC. Automated sequencing was performed to identify the underlying mutation. RESULTS: Molecular analysis indicated that in all 5 cases the correct diagnosis was autosomal recessive ATS. In three families in which parental consanguinity clearly pinpointed to autosomal recessive ATS, we found COL4A4 homozygous mutations in two of them and COL4A3 homozygous mutation in the other one. In the remaining two families a differential diagnosis including X-linked ATS, autosomal recessive ATS and thin basement membrane nephropathy was considered. The molecular analysis demonstrated that the probands were genetic compounds for two different mutations in the COL4A4 gene pinpointing to the correct diagnosis of autosomal recessive ATS. CONCLUSIONS: A clinical evaluation of probands and their relatives of the five families carrying mutations in either the COL4A3 or the COL4A4 gene was carried out to underline the natural history of the autosomal recessive ATS. In addition, this paper stresses the complexity of the clinics and genetics of ATS and how a correct diagnosis is based on a combination of: (i) an in-depth clinical investigation; (ii) a detailed formal genetic analysis; (iii) a correct technical choice of the gene to be investigated; (iv) a correct technical choice of the family member to be included in the mutational screening. A correct diagnosis is the basis for an appropriate genetic counselling dealing with both the correct prognosis and the accurate recurrence risk for the patients and family members.

CDKL5 belongs to the same molecular pathway of MeCP2 and it is responsible for the early-onset seizure variant of Rett syndrome.

Rett syndrome (RTT) is a severe neurodevelopmental disorder almost exclusively affecting females and characterized by a wide spectrum of clinical manifestations. Most patients affected by classic RTT and a smaller percentage of patients with the milder form 'preserved speech variant' have either point mutations or deletions/duplications in the MECP2 gene. Recently, mutations in the CDKL5 gene, coding for a putative kinase, have been found in female patients with a phenotype overlapping with that of RTT. Here, we report two patients with the early seizure variant of RTT, bearing two novel CDKL5 truncating mutations, strengthening the correlation between CDKL5 and RTT. Considering the similar phenotypes caused by mutations in MECP2 and CDKL5, it has been suggested that the two genes play a role in common pathogenic processes. We show here that CDKL5 is a nuclear protein whose expression in the nervous system overlaps with that of MeCP2, during neural maturation and synaptogenesis. Importantly, we demonstrate that MeCP2 and CDKL5 interact both in vivo and in vitro and that CDKL5 is indeed a kinase, which is able to phosphorylate itself and to mediate MeCP2 phosphorylation, suggesting that they belong to the same molecular pathway. Furthermore, this paper contributes to the clarification of the phenotype associated with CDKL5 mutations and indicates that CDKL5 should be analyzed in each patient showing a clinical course similar to RTT but characterized by a lack of an early normal period due to the presence of seizures.

Thin glomerular basement membrane disease: clinical significance of a morphological diagnosis--a collaborative study of the Italian Renal Immunopathology Group.

BACKGROUND: Thin glomerular basement membrane disease (TBMD) is a nephropathy defined by diffuse thinning of the glomerular basement membrane (GBM) at electron microscopy examination, without the alterations of Alport's syndrome (ATS). It is known that many patients with TBMD have a type IV collagen disorder and that the disease occasionally may be progressive. This study investigated 51 patients with the morphological diagnosis of TBMD lacking any sign of ATS, with the aim of defining the prevalence of type IV collagen mutations and the course of the disease. METHODS: Patients were investigated as follows: (a) clinical picture and family investigation; (b) renal biopsy findings; (c) immunohistochemical study of renal tissue for collagen IV alpha-chains; (d) pedigree reconstruction and molecular investigations in genes encoding type IV collagen chains, when DNA samples were available; and (e) follow-up data. RESULTS: Renal biopsy analysis revealed no light microscopy changes in 27 patients and minimal abnormalities in the remainder. Global glomerular sclerosis was found in seven cases and superimposed mesangial immunoglobulin-A deposits in four. Normal staining of GBM for alpha(IV) chains was observed in all but one patient, where alpha5(IV) was absent and molecular investigation revealed a COL4A5 mutation. Five out of 25 cases had a mutation in the COL4A3/COL4A4 genes. Eight out of 38 patients followed up for 12-240 months (21%) showed signs of disease progression or hypertension. CONCLUSIONS: This study confirms that a considerable proportion of patients with TBMD have a type IV collagen disorder and that this lesion is not always benign. Thus, families should be investigated carefully whenever possible and patients and affected relatives should be examined periodically for signs of disease progression.