Ubiquitous atmospheric production of organic acids mediated by cloud droplets.

Atmospheric acidity is increasingly determined by carbon dioxide and organic acids1-3. Among the latter, formic acid facilitates the nucleation of cloud droplets4 and contributes to the acidity of clouds and rainwater1,5. At present, chemistry-climate models greatly underestimate the atmospheric burden of formic acid, because key processes related to its sources and sinks remain poorly understood2,6-9. Here we present atmospheric chamber experiments that show that formaldehyde is efficiently converted to gaseous formic acid via a multiphase pathway that involves its hydrated form, methanediol. In warm cloud droplets, methanediol undergoes fast outgassing but slow dehydration. Using a chemistry-climate model, we estimate that the gas-phase oxidation of methanediol produces up to four times more formic acid than all other known chemical sources combined. Our findings reconcile model predictions and measurements of formic acid abundance. The additional formic acid burden increases atmospheric acidity by reducing the pH of clouds and rainwater by up to 0.3. The diol mechanism presented here probably applies to other aldehydes and may help to explain the high atmospheric levels of other organic acids that affect aerosol growth and cloud evolution.

Structural rearrangements as a recurrent pathogenic mechanism for SETBP1 haploinsufficiency.

Chromosomal structural rearrangements consist of anomalies in genomic architecture that may or may not be associated with genetic material gain and loss. Evaluating the precise breakpoint is crucial from a diagnostic point of view, highlighting possible gene disruption and addressing to appropriate genotype-phenotype association. Structural rearrangements can either occur randomly within the genome or present with a recurrence, mainly due to peculiar genomic features of the surrounding regions. We report about three non-related individuals, harboring chromosomal structural rearrangements interrupting SETBP1, leading to gene haploinsufficiency. Two out of them resulted negative to Chromosomal Microarray Analysis (CMA), being the rearrangement balanced at a microarray resolution. The third one, presenting with a complex three-chromosome rearrangement, had been previously diagnosed with SETBP1 haploinsufficiency due to a partial gene deletion at one of the chromosomal breakpoints. We thoroughly characterized the rearrangements by means of Optical Genome Mapping (OGM) and Whole Genome Sequencing (WGS), providing details about the involved sequences and the underlying mechanisms. We propose structural variants as a recurrent event in SETBP1 haploinsufficiency, which may be overlooked by laboratory routine genomic analyses (CMA and Whole Exome Sequencing) or only partially determined when associated with genomic losses at breakpoints. We finally introduce a possible role of SETBP1 in a Noonan-like phenotype.

Diagnostic accuracy of cell-free DNA in maternal blood in detecting chromosomal anomalies in twin pregnancies: systematic review and meta-analysis.

OBJECTIVES: To report the diagnostic accuracy of cell-free DNA (cfDNA) in maternal blood in detecting chromosomal anomalies in twin pregnancies. METHODS: Medline, Embase and Cochrane databases were searched. The inclusion criteria were twin pregnancies undergoing cfDNA screening for Trisomies 13, 18, 21, monosomy X0 and other sex chromosomal anomalies (SCA). The index test was represented by a positive results of cfDNA test. The reference standard was represented by the karyotype results (obtained either pre or postnatally) or, in case of negative cfDNA result, by a normal neonatal phenotype. The quality of the studies was assessed using the revised tool for the quality assessment of diagnostic accuracy studies (QUADAS-2). Summary estimates of sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR-) and diagnostic odds ratio (DOR), with the corresponding 95% Confidence Intervals (95% CI), were computed using the bivariate random-effects model. RESULTS: Thirty-five studies were included. cfDNA had an overall high accuracy in detecting Trisomy 21 in twin pregnancies with a sensitivity of 98.8% (95% CI 96.5-100), a specificity of 100% (95% CI 99.9-100). Sensitivity and specificity were of 94.9% (95% CI 75.6-99.1) and 100 (95% CI 99.9-100) for Trisomy 18, and 84.6% (95% C% 54.6-98.1) and 100% (95% CI 99.9-100) for Trisomy 13 . We could not compute the diagnostic accuracy of cfDNA in detecting monosomy X0 in twins, while cfDNA had a sensitivity of 100% (95% CI 71.5-100) and a specificity of 99.8% (95% CI 99.7-99.9) in detecting other SCA (11 cases). The accuracy of cfDNA in detecting Trisomy 21, 18 and 13 was similar in dichorionic and monochorionic twin pregnancies. CONCLUSION: cfDNA has a high diagnostic accuracy in detecting Trisomy 18 and 21 in twin pregnancies, irrespective of chorionicity. Accuracy in the detection of Trisomy 13 and SCA was limited by the small number of affected cases and the difficulties in the confirmation of false negative cases in case of SCA and requires confirmation in larger studies. This article is protected by copyright. All rights reserved.

Multiple congenital ocular anomalies in three related litters of Jack Russell Terrier puppies.

OBJECTIVE: To describe multiple congenital ocular anomalies in three litters of Jack Russell Terrier puppies. ANIMALS STUDIED: Seven purebred Jack Russell Terrier puppies from three related litters and their four parents. PROCEDURES: Medical records of the puppies and their parents were evaluated. All dogs underwent a complete ophthalmic examination, followed by bilateral ocular ultrasonography in two of the puppies with complete corneal opacity. One eye from an affected puppy was subjected to histopathology. A complete database of pedigrees was built, and individual inbreeding was evaluated. RESULTS: The most commonly diagnosed ocular anomalies in the puppies were: various anomalies of the fundus (12/14 eyes); microphthalmia (10/14 eyes); sclerocornea (8/14 eyes); and persistent pupillary membranes (7/14 eyes). Six out of seven puppies had at least two ocular abnormalities, and only one puppy was normal. Four out of seven puppies had sclerocornea, a particular corneal opacity to date described only in Spanish Podenco dogs. No ocular abnormalities were found in the parents examined (4/4). Analysis of the pedigrees showed that all the puppies and two parents were inbred, and the individual values of the inbreeding puppies were greater than 6.25% in two litters. CONCLUSIONS: Inbreeding with closely related Jack Russell Terriers may result in severe congenital eye abnormalities in puppies.

Unimolecular and water reactions of oxygenated and unsaturated Criegee intermediates under atmospheric conditions.

Ozonolysis of unsaturated hydrocarbons (VOCs) is one of the main oxidation processes in the atmosphere. The stabilized Criegee intermediates (SCI) formed are highly reactive oxygenated species that potentially influence the HOx, NOx and SOx cycles, and affect aerosol formation by yielding low-volatility oxygenated compounds. The current knowledge spans mostly SCI formed from primary emitted VOCs, but little is known about the reactivity of oxygenated SCI. In this work we present a theoretical kinetic study of a large number of unsaturated and oxygenated SCI, covering CC, OH, OR, OOH, OOOH, COOH, COOR, and ONO2 functionalities at various stereo- and site-specific substitutions relative to the SCI carbonyl oxide moiety. Several novel reaction types are covered, the most important of which are fast intramolecular insertion reactions in OH, OOH and COOH groups, or secondary ozonide formation with a COOH group, forming cyclic oxygenated species; these reaction classes are reminiscent of the analogous bimolecular reactions. The reaction with H2O molecules was likewise studied, finding that these cyclisation reactions can be catalysed, with predicted rate coefficients nearing the collision limit. The theoretical data is used to extend the structure-activity relationships (SARs) proposed by Vereecken et al. (2017), predicting the dominant unimolecular reaction class and rate, and the rates for reaction with H2O and (H2O)2. The SARs cover over 300 SCI categories with over 40 substituent categories. The validation of these SARs is discussed, and an outlook is given for further improvement. The generally short lifetime of oxygenated SCI suggests that ozonolysis of secondary, oxygenated VOCs is unlikely to yield ambient concentrations of SCI exceeding 104 cm-3 but will contribute strongly to the in situ formation of oxygenated VOCs.

Prevalence of copy number variants (CNVs) and rhGH treatment efficacy in an Italian cohort of children born small for gestational age (SGA) with persistent short stature associated with a complex clinical phenotype.

PURPOSE: Multiple factors influence intrauterine growth and lead to low birth sizes. The impact of genetic alterations on both pre- and post-natal growth is still largely unknown. The aim of this study was to investigate the prevalence of CNVs in an Italian cohort of SGA children with persistent short stature and complex clinical phenotype. rhGH treatment efficacy was evaluated according to the different genotypes. SUBJECTS AND METHODS: Twenty-four SGA children (10F/14M) with persistent short stature associated with dysmorphic features and/or developmental delay underwent CNV evaluation. RESULTS: CNVs were present in 14/24 (58%) SGA children. Six patients had a microdeletion involving the following regions: 3q24q25.1, 8p21.2p12, 15q26, 19q13.11, 20q11.21q12, 22q11.2. In three females, the same microdeletion involving 17p13.3 region was identified. In two different patients, two microduplications involving 10q21.3 and Xp11.3 region were observed. A further female patient showed both an 11q12.1 and an Xq27.1 microduplication, inherited from her mother and from her father, respectively. In a boy, the presence of a 12p13.33 microdeletion and a 19q13.43 microduplication was found. GH treatment efficacy, expressed by height gain and height velocity in the first 12 months of therapy, was similar in subjects with and without CNVs. CONCLUSIONS: These results show that pathogenic CNVs are common in SGA children with short stature associated with additional clinical features. Interestingly, the involvement of 17p13.3 region occurs with a relative high frequency, suggesting that genes located in this region could play a key role in pre- and post-natal growth. rhGH therapy has similar efficacy in the short term whether CNVs are present or not.

Experimental and theoretical study on the impact of a nitrate group on the chemistry of alkoxy radicals.

The chemistry of nitrated alkoxy radicals, and its impact on RO2 measurements using the laser induced fluorescence (LIF) technique, is examined by a combined theoretical and experimental study. Quantum chemical and theoretical kinetic calculations show that the decomposition of ß-nitrate-alkoxy radicals is much slower than ß-OH-substituted alkoxy radicals, and that the spontaneous fragmentation of the α-nitrate-alkyl radical product to a carbonyl product + NO2 prevents other ß-substituents from efficiently reducing the energy barrier. The systematic series of calculations is summarized as an update to the structure-activity relationship (SAR) by Vereecken and Peeters (2009), and shows increasing decomposition rates with higher degrees of substitution, as in the series ethene to 2,3-dimethyl-butene, and dominant H-migration for sufficiently large alkoxy radicals such as those formed from 1-pentene or longer alkenes. The slow decomposition allows other reactions to become competitive, including epoxidation in unsaturated nitrate-alkoxy radicals; the decomposition SAR is likewise updated for ß-epoxy substituents. A set of experiments investigating the NO3-initiated oxidation of ethene, propene, cis-2-butene, 2,3-dimethyl-butene, 1-pentene, and trans-2-hexene, were performed in the atmospheric simulation chamber SAPHIR with measurements of HO2 and RO2 radicals performed with a LIF instrument. Comparisons between modelled and measured HO2 radicals in all experiments, performed in excess of carbon monoxide to avoid OH radical chemistry, suggest that the reaction of HO2 with ß-nitrate alkylperoxy radicals has a channel forming OH and an alkoxy radical in yields of 15-65%, compatible with earlier literature data on nitrated isoprene and α-pinene radicals. Model concentrations of RO2 radicals when including the results of the theoretical calculations described here, agreed within 10% with the measured RO2 radicals for all species investigated when the alkene oxidation is dominated by NO3 radicals. The formation of NO2 in the decomposition of ß-nitrate alkoxy radicals prevents detection of the parent RO2 radical in a LIF instrument, as it relies on formation of HO2. The implications for measurements of RO2 in ambient and experimental conditions, such as for the NO3-dominated chemistry during nighttime, is discussed. The current results appear in disagreement with an earlier indirect experimental study by Yeh et al. on pentadecene.

Theoretical and experimental study of peroxy and alkoxy radicals in the NO3-initiated oxidation of isoprene.

The initial stages of the nitrate radical (NO3) initiated oxidation of isoprene, in particular the fate of the peroxy (RO2) and alkoxy (RO) radicals, are examined by an extensive set of quantum chemical and theoretical kinetic calculations. It is shown that the oxidation mechanism is highly complex, and bears similarities to its OH-initiated oxidation mechanism as studied intensively over the last decade. The nascent nitrated RO2 radicals can interconvert by successive O2 addition/elimination reactions, and potentially have access to a wide range of unimolecular reactions with rate coefficients as high as 35 s-1; the contribution of this chemistry could not be ascertained experimentally. The chemistry of the alkoxy radicals derived from these peroxy radicals is affected by the nitrate moiety, and can lead to the formation of nitrated epoxy peroxy radicals in competition with isomerisation and decomposition channels that terminate the organic radical chain by NO2 elimination. The theoretical predictions are implemented in the FZJ-NO3-isoprene mechanism for NO3-initiated atmospheric oxidation of isoprene. The model predictions are compared against peroxy radical (RO2) and methyl vinyl ketone (MVK) measurements in a set of experiments on the isoprene + NO3 reaction system performed in the SAPHIR environmental chamber (IsopNO3 campaign). It is shown that the formation of NO2 from the peroxy radicals can prevent a large fraction of the peroxy radicals from being measured by the laser-induced fluorescence (ROxLIF) technique that relies on a quantitative conversion of peroxy radicals to hydroxyl radicals. Accounting for the relative conversion efficiency of RO2 species in the experiments, the agreement between observations and the theory-based FZJ-NO3-isoprene model predictions improves significantly. In addition, MVK formation in the NO3-initiated oxidation was found to be suppressed by the epoxidation of the unsaturated RO radical intermediates, allowing the model-predicted MVK concentrations to be in good agreement with the measurements. The FZJ-NO3-isoprene mechanism is compared against the MCM v3.3.1 and Wennberg et al. (2018) mechanisms.

Immunofluorescence mapping, electron microscopy and genetics in the diagnosis and sub-classification of inherited epidermolysis bullosa: a single-centre retrospective comparative study of 87 cases with long-term follow-up.

BACKGROUND: Epidermolysis bullosa (EB) comprises a heterogeneous group of skin fragility disorders, classified in four major types based on skin cleavage level, i.e. EB simplex (EBS), junctional EB (JEB), dystrophic EB (DEB), Kindler EB, and in more than 30 subtypes defined by the combination of laboratory and clinical data, including disease course. OBJECTIVES: Our aims were to address whether, in the age of genomics, electron microscopy (TEM) has still a role in diagnosing EB, and whether the genotype per se may be sufficient to sub-classify EB. METHODS: A thoroughly characterized single-centre EB case series was retrospectively evaluated to compare the power of TEM with immunofluorescence mapping (IFM) in establishing the EB type, and the ability of TEM, IFM and genetics to predict selected EB subtypes, i.e. severe dominant EBS (DEBS), severe JEB, severe recessive DEB (RDEB) and DEB self-improving, using genetic and final diagnosis, respectively, as gold standard. RESULTS: The series consisted of 87 patients, including 44 newborns, with a median follow-up of 54 months. Ninety-five mutations were identified in EB-associated genes, including 25 novel variants. Both IFM and TEM were diagnostic in about all cases of JEB (21/21 for both) and DEB (43/44 for IFM, 44/44 for TEM). TEM sensitivity was superior to IFM for EBS (19/20 vs. 16/19). As to EB subtyping, IFM performed better than genetics in identifying severe JEB cases due to laminin-332 defect (14/14 vs. 10/14) and severe RDEB (eight/nine vs. seven/nine). Genetics had no role in self-improving DEB diagnosis; it almost equalled TEM in predicting severe DEBS (eight/nine vs. nine/nine) and enabled to discriminate dominant from recessive non-severe DEB phenotypes and to identify special subtypes, e.g. DEBS with KLHL24 mutations. CONCLUSIONS: Transmission electron microscopy remains relevant to the diagnosis of EBS. IFM and genetics are essential and complementary tools in the vast majority of EB cases.

Correction to: Structural modeling of a novel TERC variant in a patient with aplastic anemia and short telomeres.

The original version of this article contained a mistake in the affiliation of E. Bellacchio. Correct affiliation is presented here.

Intrafamiliar clinical variability of circumferential skin creases Kunze type caused by a novel heterozygous mutation of N-terminal TUBB gene.

Circumferential skin creases Kunze type (CSC-KT; OMIM 156610, 616734) is a rare disorder characterized by folding of excess skin, which leads to ringed creases, known as Michelin Tire Baby Syndrome (MTBS). CSC-KT patients also exhibit facial dysmorphism, growth retardation, intellectual disability (ID) and multiple congenital malformations. Recently, 2 heterozygous mutations in TUBB gene and 4 mutations (both homozygous and heterozygous) in MAPRE2 gene were identified in 3 and 4 CSC-KT patients, respectively. In the 3 TUBB gene-related CSC-KT patients, all mutations fall in the N-terminal gene domain and were de novo. Mutations in the C-terminal of TUBB gene have been associated to microcephaly and structural brain malformation, in the absence of CSC-KT features. We report a 9-year-old boy with a diagnosis of CSC-KT based on MTBS, facial dysmorphism, microcephaly, severe ID, cortical atrophy and corpus callosum hypoplasia. Sanger sequencing identified a novel heterozygous c.218T>C (p.Met73Thr) mutation in the N-terminal of TUBB gene, that was inherited from the mother affected by isolated MTBS. This is the first report of inherited TUBB gene-related CSC-KT resulting from a novel heterozygous mutation in the N-terminal domain. Present data support the role of TUBB mutations in CSC-KT and definitely includes CSC-KT syndrome within the tubulinopathies.

Expanding the clinical and molecular spectrum of PRMT7 mutations: 3 additional patients and review.

Protein arginine methyltransferase 7 (PRMT7) is a member of a family of enzymes that catalyze the transfer of methyl groups from S-adenosyl-l-methionine to nitrogen atoms on arginine residues. Arginine methylation is involved in multiple biological processes, such as signal transduction, mRNA splicing, transcriptional control, DNA repair, and protein translocation. Currently, 7 patients have been described harboring compound heterozygous or homozygous variants in the PRMT7 gene, causing a novel intellectual disability syndrome, known as SBIDDS syndrome (Short Stature, Brachydactyly, Intellectual Developmental Disability, and Seizures). We report on 3 additional patients from 2 consanguineous families with severe/moderate intellectual disability, short stature, brachydactyly and dysmorphisms. Exome sequencing revealed 2 novel homozygous mutations in PRMT7. Our findings expand the clinical and molecular spectrum of homozygous PRMT7 mutations, associated to the SBIDDS syndrome, showing a possible correlation between the type of mutation and the severity of the phenotype.

A recognizable systemic connective tissue disorder with polyvalvular heart dystrophy and dysmorphism associated with TAB2 mutations.

Deletions encompassing TAK1-binding protein 2 (TAB2) associated with isolated and syndromic congenital heart defects. Rare missense variants are found in patients with a similar phenotype as well as in a single individual with frontometaphyseal dysplasia. We describe a family and an additional sporadic patient with polyvalvular heart disease, generalized joint hypermobility and related musculoskeletal complications, soft, velvety and hyperextensible skin, short limbs, hearing impairment, and facial dysmorphism. In the first family, whole-exome sequencing (WES) disclosed the novel TAB2 c.1398dup (p.Thr467Tyrfs*6) variant that eliminates the C-terminal zinc finger domain essential for activation of TAK1 (TGFß-activated kinase 1)-dependent signaling pathways. The sporadic case carryed a ~2 Mb de novo deletion including 28 genes also comprising TAB2. This study reveal an association between TAB2 mutations and a phenotype resembling Ehlers-Danlos syndrome with severe polyvalvular heart disease and subtle facial dysmorphism. Our findings support the existence of a wider spectrum of clinical phenotypes associated with TAB2 perturbations and emphasize the role of TAK1 signaling network in human development.

Unimolecular decay strongly limits the atmospheric impact of Criegee intermediates.

Stabilized Criegee intermediates (SCI) are reactive oxygenated species formed in the ozonolysis of hydrocarbons. Their chemistry could influence the oxidative capacity of the atmosphere by affecting the HOx and NOx cycles, or by the formation of low-volatility oxygenates enhancing atmospheric aerosols known to have an important impact on climate. The concentration of SCI in the atmosphere has hitherto not been determined reliably, and very little is known about their speciation. Here we show that the concentration of biogenic SCI is strongly limited by their unimolecular decay, based on extensive theory-based structure-activity relationships (SARs) for the reaction rates for decomposition. Reaction with water vapor, H2O and (H2O)2 molecules, is the second most important loss process; SARs are also proposed for these reactions. For SCI derived from the most common biogenic VOCs, we find that unimolecular decay is responsible for just over half of the loss, with reaction with water vapor the main remaining loss process. Reactions with SO2, NO2, or acids have negligible impact on the atmospheric SCI concentration. The ambient SCI concentrations are further characterized by analysis of field data with speciated hydrocarbon information, and by implementation of the chemistry in a global chemistry model. The results show a highly complex SCI speciation, with an atmospheric peak SCI concentrations below 1 × 105 molecule cm-3, and annual average SCI concentrations less than 7 × 103 molecule cm-3. We find that SCI have only a negligible impact on the global gas phase H2SO4 formation or removal of oxygenates, though some contribution around the equatorial belt, and in select regions, cannot be excluded.

The reactions of Criegee intermediates with alkenes, ozone, and carbonyl oxides.

The reaction of Criegee intermediates with a number of coreactants is examined using theoretical methodologies, combining ROCCSD(T)//M06-2X quantum calculations with theoretical kinetic predictions of the rate coefficients. The reaction of CI with alkenes is found to depend strongly on the substitutions in the reactants, resulting in significant differences in the predicted rate coefficient as a function of the selected alkene and CI. Despite submerged barriers, these entropically disfavored reactions are not expected to affect CI chemistry. The reaction of H2COO + H2COO is found to be barrierless, with a rate coefficient nearing the collision limit, ≥4 × 10(-11) cm(3) molecule(-1) s(-1). The dominant reaction products are expected to be carbonyl compounds and an oxygen molecule, though chemically activated reactions may give rise to a plethora of different (per)acids and carbonyl compounds. CI + CI reactions are expected to be important only in laboratory environments with high CI concentrations. The reaction of H2COO with O3 was predicted to proceed through a pre-reactive complex and a submerged barrier, with a rate coefficient of 1 × 10(-12) cm(3) molecule(-1) s(-1). A study of the dominant CI reactions under experimental and atmospheric conditions shows that the latter reaction might affect CI chemistry.

Direct observation of OH formation from stabilised Criegee intermediates.

The syn-CH3CHOO Criegee intermediate formed from the ozonolysis of propene and (E)-2-butene was detected via unimolecular decomposition and subsequent detection of OH radicals by a LIF-FAGE instrument. An observed time dependent OH concentration profile was analysed using a detailed model focusing on the speciated chemistry of Criegee intermediates based on the recent literature. The absolute OH concentration was found to depend on the steady state concentration of syn-CH3CHOO at the injection point while the time dependence of the OH concentration profile was influenced by the sum of the rates of unimolecular decomposition of syn-CH3CHOO and wall loss. By varying the most relevant parameters influencing the SCI chemistry in the model and based on the temporal OH concentration profile, the unimolecular decomposition rate k (293 K) of syn-CH3CHOO was shown to lie within the range 3-30 s(-1), where a value of 20 ± 10 s(-1) yields the best agreement with the CI chemistry literature.

Intractable diarrhea in infancy and molecular analysis: We are beyond the tip of the iceberg.

BACKGROUND: Intractable diarrhea (ID) could be defined as a syndrome of severe chronic diarrhea associated with malnutrition not easily resolved by conventional management. AIMS: To provide an overview on etiology and management of ID patients in Italy in the last 12 years. METHODS: The members of Italian Society for Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP) enrolled all ID patients seen between January 1, 2011 and December 31, 2022. RESULTS: 69 children were enrolled (49 M, 20 F; median age at ID onset 9.5 days) from 7 tertiary care pediatric centers. Overall 62 patients had genetic diseases; 3 had infantile Inflammatory Bowel Disease and 1 autoimmune enteropathy in absence of genetic mutations; 2 undefined ID. Defects of intestinal immune-related homeostasis caused ID in 29 patients (42 %). CONCLUSION: ID is a rare but challenging problem, although the potential for diagnosis has improved over time. In particular, molecular analysis allowed to identity genetic defects in 90 % of patients and to detect new genetic mutations responsible for ID. Due to both the challenging diagnosis and the treatment for many of these diseases, the close relationship between immune system and digestive tract should require a close collaboration between pediatric immunologists and gastroenterologists, to optimize epidemiologic surveillance and management of ID.

Syndromic non-compaction of the left ventricle: associated chromosomal anomalies.

Non-compaction of the left ventricle (NCLV) is a cardiomyopathy characterized by prominent left ventricular trabeculae and deep intertrabecular recesses. Associated extracardiac anomalies occur in 14-66% of patients of different series, while chromosomal anomalies were reported in sporadic cases. We investigated the prevalence of chromosomal imbalances in 25 syndromic patients with NCLV, using standard cytogenetic, subtelomeric fluorescent in situ hybridization, and array-comparative genomic hybridization (CGH) analyses. Standard chromosome analysis disclosed an abnormality in three (12%) patients, including a 45,X/46,XX mosaic, a 45,X/46,X,i(Y)(p11) mosaic, and a de novo Robertsonian 13;14 translocation in a child affected by hypomelanosis of Ito. Cryptic chromosome anomalies were found in six (24%) cases, including 1p36 deletion in two patients, 7p14.3p14.1 deletion, 18p subtelomeric deletion, 22q11.2 deletion associated with velo-cardio-facial syndrome, and distal 22q11.2 deletion, each in one case. These results recommend accurate clinical evaluation of patients with NCLV, and suggest that chromosome anomalies occur in about one third of syndromic NCLV individuals, without metabolic/neuromuscular disorder. Array-CGH analysis should be included in the diagnostic protocol of these patients, because different submicroscopic imbalances are causally associated with this disorder and can pinpoint candidate genes for this cardiomyopathy.