BACKGROUND:Primary Ciliary Dyskinesia (PCD) is a rare, genetically heterogeneous disorder. Despite the increasing number of identified causative genes, 20-30% of patients still lack a genetic diagnosis. To date, genetic analyses have primarily focused on single nucleotide variants (SNVs). In this study, we evaluated whether the detection of copy number variants (CNVs) improves the diagnostic yield in our large patient cohort. METHODS:We retrospectively evaluated patients with confirmed or suspected PCD who remained genetically unresolved after next-generation sequencing (NGS). CNV analysis was performed using a custom high-density array comparative genomic hybridization (aCGH) platform targeting known PCD-associated genes. RESULTS:A total of 203 patients with a clinically compatible PCD phenotype were included. NGS-based testing identified pathogenic variants in 175 cases (86.2%). The remaining 28 patients underwent aCGH analysis, which identified CNVs involving PCD-associated genes in 13 cases. Detected variants included homozygous deletions in DNAAF4, CFAP300, and CCDC39, a hemizygous deletion in DNAAF6, and heterozygous CNVs in SPAG1, ODAD4, ODAD1, DNAI2, DNAH11, and DNAH5, in combination with SNVs previously identified by NGS. The pathogenicity of these variants was supported by in silico predictions and was consistent with ciliary ultrastructural and functional abnormalities. Integration of aCGH increased the overall diagnostic yield to 92.6%. CONCLUSIONS:Targeted CNV analysis by custom aCGH increases diagnostic yield in PCD, with potential benefits for earlier diagnosis and treatment, and should be routinely implemented.

We describe the case of a NUT carcinoma of the thorax in a 27-year-old male, non-smoker, presenting a voluminous neoformation in the hilum and the left side of the mediastinum infiltrating heart and great vessels. The biopsy revealed a poorly differentiated cancer with focal crush artifact consisting of undifferentiated small to medium-size cells, with minimal indistinct to clear cytoplasm, round or oval nuclei, nuclear molding and brisk mitotic activity. Suggestive morphological features often associated with NUT carcinoma, for example abrupt foci of keratinization, were not seen. Moreover, immunohistochemical (IHC) analysis showed negativity for epithelial markers, such as Cytokeratin AE1/AE3, CK7, CK-CAM5.2, CK5/6, p40 and TTF1; therefore, further immunohistochemical markers were evaluated, and the conclusive diagnosis was based on a diffuse speckled nuclear positivity for NUT1 (clone C52B1). Considering the unusual morphological and IHC findings, a comprehensive genome profiling, by FoundationOne®CDx Next Generation Sequencing (NGS), was performed on DNA from the transbronchial needle aspiration formalin-fixed and paraffin-embedded cell block. Neither NUTM1 gene fusions nor other pathogenic gene variants were detected. However, focal and segmental copy number variations (CNV) were seen in chromosome 19, in the middle of the BRD4 gene, the most common NUTM1 fusion partner. In addition, an array CGH (aCGH) analysis was performed: this analysis revealed different CNV, including a 2.7Mb deletion and a 14.4Mb duplication in chromosome regions were NUTM1 and BRD4 are respectively located. Finally, an RNA-based NGS confirmed the presence of a BDR4-NUTM1 fusion transcript, supporting IHC findings. IHC and molecular results all together are suggestive for a likely non-canonical BRD4-NUTM1 fusion. Our case showed unusual features both from a morphological and a molecular point of view: the diagnosis was driven by NUT1 positive immunohistochemistry, thus underlining the crucial role of this test.

22q11.2 is a region prone to chromosomal rearrangements due to the presence of eight large blocks of low-copy repeats (LCR22s). The 3 Mb 22q11.2 “typical deletion”, between LCR22-A and D, causes a fairly well-known clinical picture, while the effects of smaller CNVs harbored in this interval are still to be fully elucidated. Nested deletions, flanked by LCR22B-D, LCR22B-C, or LCR22C-D, are very rare and are collectively described as “central deletions”. The LCR22C-D deletion (CDdel) has never been separately analyzed. In this paper, we focused only on CDdel, evaluating its gene content and reviewing the literature and public databases in order to obtain new insights for the classification of this CNV. At first glance, CDdels are associated with a broad phenotypic spectrum, ranging from clinically normal to quite severe phenotypes. However, the frequency of specific clinical traits highlights that renal/urinary tract abnormalities, cardiac defects, and neurological/behavioral disorders are much more common in CDdel than in the general population. This frequency is too high to be fortuitous, indicating that CDdel is a predisposing factor for these phenotypic traits. Among the genes present in this interval, CRKL is an excellent candidate for cardiac and renal defects. Even if further data are necessary to confirm the role of CDdels, according to our review, this CNV fits into the class of ‘likely pathogenic’ CNVs.

OBJECTIVE:Primary ciliary dyskinesia (PCD) severity has been related to genotype and levels of nasal nitric oxide (nNO). The most common TAS2R38 haplotypes (PAV/PAV, PAV/AVI, AVI/AVI) encoding the bitter taste receptor can affect nNO levels and thus could play a role in the susceptibility to respiratory infections. We assessed the impact of these polymorphisms on nNO production and Pseudomonas aeruginosa (P.a.) infections in different PCD genotypes. METHODS:Prospective, longitudinal, single-centre study in patients with PCD with known genotype and one of three TAS2R38 haplotypes evaluated for up to 10 years. We related nNO values to TAS2R38 haplotypes in all patients, and in the three most frequent genotypes (CCDC39/CCDC40, DNAH5, DNAH11). In the genetic group(s) with different mean trends of nNO in relation to the polymorphism, we evaluated longitudinal lung function as a clinical outcome measure. We also studied any associations between the prevalence of chronic P.a. infection and PAV alleles. Linear mixed-effects models were used to evaluate longitudinal associations. RESULTS:119 patients with PCD underwent 1116 study visits. Only in the DNAH11 mutations group was there a mean trend of nNO production which was significantly higher in PAV/PAV than AVI/AVI haplotype (p=0.033), with a better trend in spirometric and plethysmographic parameters. In patients with DNAH11 mutations the PAV allele was also associated with a significantly reduced prevalence of chronic P.a. INFECTION: CONCLUSION:TAS2R38 may be a modifier gene for PCD severity, but only in mild phenotype disease. Further study of TAS2R38 polymorphisms might enable new management strategies to prevent chronic P.a. INFECTIONS:

BACKGROUND:International guidelines disagree on how best to diagnose primary ciliary dyskinesia (PCD), not least because many tests rely on pattern recognition. We hypothesized that quantitative distribution of ciliary ultrastructural and motion abnormalities would detect most frequent PCD-causing groups of genes by soft computing analysis.METHODS:Archived data on transmission electron microscopy and high-speed video analysis from 212 PCD patients were re-examined to quantitate distribution of ultrastructural (10 parameters) and functional ciliary features (4 beat pattern and 2 frequency parameters). The correlation between ultrastructural and motion features was evaluated by blinded clustering analysis of the first two principal components, obtained from ultrastructural variables for each patient. Soft computing was applied to ultrastructure to predict ciliary beat frequency (CBF) and motion patterns by a regression model. Another model classified the patients into the five most frequent PCD-causing gene groups, from their ultrastructure, CBF and beat patterns.RESULTS:The patients were subdivided into six clusters with similar values to homologous ultrastructural phenotype, motion patterns, and CBF, except for clusters 1 and 4, attributable to normal ultrastructure. The regression model confirmed the ability to predict functional ciliary features from ultrastructural parameters. The genetic classification model identified most of the different groups of genes, starting from all quantitative parameters.CONCLUSIONS:Applying soft computing methodologies to PCD diagnostic tests optimizes their value by moving from pattern recognition to quantification. The approach may also be useful to evaluate atypical PCD, and novel genetic abnormalities of unclear disease-producing potential in the future.

Disorders of sexual development (DSDs) encompass a group of congenital conditions associated with atypical development of internal and external genital structures. Among those with DSDs are 46,XX males, whose condition mainly arises due to the translocation of SRY onto an X chromosome or an autosome. In the few SRY-negative 46,XX males, overexpression of other pro-testis genes or failure of pro-ovarian/anti-testis genes may be involved, even if a non-negligible number of cases remain unexplained. A three-year-old boy with an SRY-negative 46,XX karyotype showed a normal male phenotype and normal prepubertal values for testicular hormones. A heterozygous de novo in tandem duplication of 50,221 bp, which encompassed exons 2 and 3 of the Doublesex and Mab-3-related transcription factor 1 (DMRT1) gene, was detected using MPLA, CGH-array analysis, and Sanger sequencing. Both breakpoints were in the intronic regions, and this duplication did not stop or shift the coding frame. Additional pathogenic or uncertain variants were not found in a known pro-testis/anti-ovary gene cascade using a custom NGS panel and whole genome sequencing. The duplication may have allowed DMRT1 to escape the transcriptional repression that normally occurs in 46,XX fetal gonads and thus permitted the testicular determination cascade to switch on. So far, no case of SRY-negative 46,XX DSD with alterations in DMRT1 has been described.

Somatic copy number alterations (SCNA) involving either a whole chromosome or just one of the arms, or even smaller parts, have been described in about 88% of human tumors. This study investigated the SCNA profile in 40 well-characterized sporadic medullary thyroid carcinomas by comparative genomic hybridization array. We found that 26/40 (65%) cases had at least one SCNA. The prevalence of SCNA, and in particular of chromosome 3 and 10, was significantly higher in cases with a RET somatic mutation. Similarly, SCNA of chromosomes 3, 9, 10 and 16 were more frequent in cases with a worse outcome and an advanced disease. By the pathway enrichment analysis, we found a mutually exclusive distribution of biological pathways in metastatic, biochemically persistent and cured patients. In particular, we found gain of regions involved in the intracellular signaling and loss of regions involved in DNA repair and TP53 pathways in the group of metastatic patients. Gain of regions involved in the cell cycle and senescence were observed in patients with biochemical disease. Finally, gain of regions associated with the immune system and loss of regions involved in the apoptosis pathway were observed in cured patients suggesting a role of specific SCNA and corresponding altered pathways in the outcome of sporadic MTC.

The clinical expression of 22q11.2 deletion syndrome (22q11.2 DS) is extremely variable, as patients can present with recurrent or severe infections, immune dysregulation, atopic diseases, or extra-immunological manifestations. The immunological background underlying the different disease manifestations is not completely elucidated. The aim of this study was to identify the immunophenotypic peculiarities of 22q11.2 DS patients presenting with different disease expressions. This study included 34 patients with 22q11.2 DS, divided into three groups according to the clinical phenotype: isolated extra-immunological manifestations (G1), infectious phenotype with increased/severe infections (G2), and immune dysregulation (G3). The patients underwent extended immunophenotyping of the T and B lymphocytes and analysis of the circulating dendritic cells (DCs). In patients with an infectious phenotype, a significant reduction in CD3+ and CD4+ cells and an expansion of CD8 naïve cells was evidenced. On the other hand, the immunophenotype of the patients with immune dysregulation showed a skewing toward memory T cell populations, and reduced levels of recent thymic emigrants (RTEs), while the highest levels of RTEs were detected in the patients with isolated extra-immunological manifestations. This study integrates the current literature, contributing to elucidating the variability in the immune status of patients with 22q11.2DS with different phenotypic expressions, particularly in those with infectious phenotype and immune dysregulation.

Background and objectives: Otoferlin is a multi-C2 domain protein implicated in neurotransmitter-containing vesicle release and replenishment of the cochlear inner hair cell (IHC) synapses. Mutations in the OTOF gene have been associated with two different clinical phenotypes: a prelingual severe-to-profound sensorineural hearing loss (ANSD-DFNB9); and the peculiar temperature-sensitive auditory neuropathy (TS-ANSD), characterized by a baseline mild-to-moderate hearing threshold that worsens to severe-to-profound when the body temperature rises that returns to a baseline a few hours after the temperature has fallen again. The latter clinical phenotype has been described only with a few OTOF variants with an autosomal recessive biallelic pattern of inheritance. Case report: A 7-year-old boy presented a picture compatible with TS-ANSD exacerbated by febrile states or physical exercise with mild-to-moderate hearing loss at low and medium frequencies and a decrease in speech discrimination that worsened with an unfavorable speech-to-noise ratio. Otoacoustic emissions (OAEs) were present whereas auditory brainstem responses (ABRs) evoked by a click or tone-burst were generally absent. No inner ear malformations were described from the CT scan or MRI. Next-generation sequencing (NGS) of the known deafness genes and multi-phasic bioinformatic analyses of the data detected in OTOF a c.2521G>A missense variant and the deletion of 7.4 Kb, which was confirmed by array-comparative genomic hybridization (array-CGH). The proband’s parents, who were asymptomatic, were tested by Sanger sequencing and the father presented the c.2521G>A missense variant. Conclusions: The picture presented by the patient was compatible with OTOF-induced TS-ANSD. OTOF has been generally associated with an autosomal recessive biallelic pattern of inheritance; in this clinical report, two pathogenic variants never previously associated with TS-ANSD were described.

Introduction Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairment in social interaction and communication, whose etiology is heterogeneous, including genetic, epigenetic, and environmental factors. It is associated with restricted interests and stereotyped behaviors with high prevalence rates in general population, neurobiological bases and high heritability. Objectives The aim of our study is to identify the possible phenotype-genotype relationships regarding neurodevelopmental disorders and to evaluate a correlation between genomic alterations and the manifestations of the overt and subthreshold ASD in a family administered psychiatric clinical evaluations at our hospital. Methods The family M underwent a psychiatric evaluation through the MINI interview according to the SCID-5 criteria, the AQ, ADAS, PAS-SR, SHI-SHY,SHY-OBS to assess respectively the subthreshold traits of ASD in adulthood, the panic-agoraphobic, social-phobic and obsessive-compulsive spectrum and CAT-Q Italian version, to evaluate social camouflage behaviors typical of ASD individuals. Array Comparative Genomic Hybridization was used for studying DNA imbalances in this family. Results We found that Mrs.A, her father, her brothers and her older sister had a microduplication, very likely pathogenic, since it has been never reported in healthy subjects and harbors several genes. It could be related with overt and subthreshold traits of ASD. From the questionnaires administered and from the clinical interview, it emerged that Mrs.A is affected by ASD and Bipolar Disorder. Her twin brothers have been evaluated at early ages by child neuropsychiatric clinic and they were diagnosed with ASD and mental and psychomotor impairment. Her father was reported a significant trend in ADAS, AQ, PAS-SR, SHI-SHY and SHY-OBS scores. Finally, about her older sister, even if our results were not significant for an ASD diagnosis, we speculated that she performed a high score in some ADAS items and in the CAT-Q but not in the AQ. Females generally tend to attract fewer attention than males thanks to their better coping and camouflaging mechanisms as well as their ability to “disappear” in large groups. Conclusions Genetic knowledge can have a relevant clinical impact; a genetic etiology can be identified in individuals with ASD, leading to the identification of treatable psychiatric comorbidities. Furthermore, knowing the causative genetic variants of ASD could provide crucial information for genetic counseling as well as to understand the neurobiology of these disorders and to contribute to an early diagnosis. Disclosure of Interest None Declared

Autism spectrum disorder (ASD) is characterized by multifactorial etiology and high heritability but can be challenging to be diagnosed, especially in cases presenting subthreshold symptoms with no cognitive or language impairment, which may not be identified until adulthood but may occur in family members of subjects with ASD. This study explores the possible correlation between a genomic imbalance and clinical phenotypes in a family case of a proband with ASD, with subjects presenting full-blown or subthreshold ASD and/or mood disorders. Clinical assessments were carried out by means of the Structured Clinical Interview for DSM-5 (SCID-5) disorders, Autism Spectrum Quotient (AQ), Autism Diagnostic Interview–Revised (ADI-R), Autism Diagnostic Observation Schedule Module 2 (ADOS-2), and Adult Autism Subthreshold Spectrum (AdAS Spectrum). The genetic evaluation included array comparative genomic hybridization (array-CGH). The proband was diagnosed with ASD and bipolar disorder type I (BD-I), her twin brothers with ASD and intellectual disability (ID), and her father and sister with BD type II (BD-II) and autism traits. The proband, her father, twin brothers, and older sister showed a microduplication of 350 kb in 20q11.21. In contrast, the proband’s mother did not present the microduplication or any mental disorder. This study reports a microduplication that segregates with family members affected by ASD or autistic traits comorbid in some cases with bipolar disorder, and that has never been reported in healthy subjects. Among the genes harbored in this region, the TM9SF4 gene has been recently implicated in risk for ASD.

The NFIA (nuclear factor I/A) gene encodes for a transcription factor belonging to the nuclear factor I family and has key roles in various embryonic differentiation pathways. In humans, NFIA is the major contributor to the phenotypic traits of "Chromosome 1p32p31 deletion syndrome". We report on two new cases with deletions involving NFIA without any other pathogenic protein-coding gene alterations. A cohort of 24 patients with NFIA haploinsufficiency as the sole anomaly was selected by reviewing the literature and public databases in order to analyze all clinical features reported and their relative frequencies. This process was useful because it provided an overall picture of the phenotypic outcome of NFIA haploinsufficiency and helped to define a cluster of phenotypic traits that can facilitate clinicians in identifying affected patients. NFIA haploinsufficiency can be suspected by a careful observation of the dysmorphisms (macrocephaly, craniofacial, and first-finger anomalies), and this potential diagnosis is strengthened by the presence of intellectual and developmental disabilities or other neurodevelopmental disorders. Further clues of NFIA haploinsufficiency can be provided by instrumental tests such as MRI and kidney urinary tract ultrasound and confirmed by genetic testing.

Background: Poirier–Bienvenu Neurodevelopmental Syndrome (POBINDS) is a rare disease linked to mutations of the CSNK2B gene, which encodes for a subunit of caseinkinase CK2 involved in neuronal growth and synaptic transmission. Its main features include early-onset epilepsy and intellectual disability. Despite the lack of cases described, it appears that POBINDS could manifest with a wide range of phenotypes, possibly related to the different mutations of CSNK2B. Methods: Our multicentric, retrospective study recruited nine patients with POBINDS, detected using next-generation sequencing panels and whole-exome sequencing. Clinical, laboratory, and neuroimaging data were reported for each patient in order to assess the severity of phenotype, and eventually, a correlation with the type of CSNK2B mutation. Results: We reported nine unrelated patients with heterozygous de novo mutations of the CSNK2B gene. All cases presented epilepsy, and eight patients were associated with a different degree of intellectual disability. Other features detected included endocrinological and vascular abnormalities and dysmorphisms. Genetic analysis revealed six new variants of CSNK2B that have not been reported previously. Conclusion: Although it was not possible to assess a genotype–phenotype correlation in our patients, our research further expands the phenotype spectrum of POBINDS patients, identifying new mutations occurring in the CSNK2B gene.

(Abstracted from Prenat Diagn 2022;42:1575–1586 Methods for diagnosis of genetic abnormalities have recently undergone substantial improvement. Noninvasive prenatal testing (NIPT) is performed early in pregnancy, typically at the end of the first trimester using cell-free DNA (cfDNA) to identify 3 commonly occurring trisomies (13, 18, and 21).

BACKGROUND: We hypothesized that differences in nasal nitric oxide (nNO) and fractional exhaled nitric oxide (FENO) relate to prognosis in primary ciliary dyskinesia (PCD). RESEARCH QUESTION: What is the relationship between baseline values and longitudinal evolution of nNO and FENO and ultrastructure, genotype, and respiratory infections in PCD? STUDY DESIGN AND METHODS: Prospective, longitudinal, single-center study in adults and children evaluated biannually for up to 10 years. We compared cross-sectional and longi-tudinal values of nNO and FENO in ultrastructural (inner dynein arm [IDA] and microtubular disorganization [MTD]) and genetic (CCDC39 and CCDC40) groups known to have worse pulmonary function with patients within the ultrastructural and genetic groups with a better prognosis. Linear mixed-effects models were used to evaluate longitudinal associations. RESULTS: One hundred forty-one patients with PCD underwent 1,014 visits. At enrollment, no differences were found in children in nNO or FENO between the IDA and MTD group and the other ultrastructural groups. In adults, nNO (P = .038) and FENO (P = .032) were significantly lower in the IDA and MTD group than in all other combined ultrastructural groups. FENO values were significantly lower in the CCDC39 and CCDC40 group than in the DNAH5 and DNAH11 combined genotype group (P = .033) and in all other genotypes (P = .032). The IDA and MTD group showed a significant decline in nNO with age (P < .01) compared with other ultrastructural groups who showed stable levels. The CCDC39 and CCDC40 group showed the steepest decline in nNO over time (P < .01) compared with all other genotypes. A higher nNO was associated with lower likelihood of any positive bacterial isolate from the lower respiratory tract (P = .008). Changes in FENO over time did not differ between structural groups or genotypes.

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Chromosome 22q11.2 deletion syndrome (22q11.2DS) is a primary immunodeficiency characterized by a broad and heterogeneous clinical presentation associated with various degrees of T-cell deficiency. We report the clinical, immunologic, and genetic findings of a cohort of eight patients presenting with a clinical phenotype that is highly suggestive of this syndrome but without the 22q11.2 deletion. The cardinal features of 22q11.2DS, such as congenital heart defects, hypoparathyroidism, and facial dysmorphisms, were observed in the majority of the patient cohort. The unusual features are described in detail. The immunologic assessment showed various degrees of immunodeficiency of the T-cell compartment, notably a reduction in the thymic output. Half of the patient cohort exhibited a reduction in total dendritic cells. Array comparative genomic hybridization (CGH) revealed six patients harboring copy number variations (CNVs) never reported in normal subjects. The gene content of these CNVs was carefully analyzed to understand the mechanisms leading to 22q11.2DS phenocopies. According to these results, we suggested that array-CGH should be used as a first-tier tool for patients resembling 22q11.2DS.

Neurodevelopmental disorders (NDDs) are considered synaptopathies, as they are due to anomalies in neuronal connectivity during development. DLG2 is a gene involved insynaptic function; the phenotypic effect of itsalterations in NDDs has been underestimated since few cases have been thoroughly described.We report on eight patients with 11q14.1 imbalances involving DLG2, underlining its potential effects on clinical presentation and its contribution to NDD comorbidity by accurate neuropsychiatric data collection. DLG2 is a very large gene in 11q14.1, extending over 2.172 Mb, with alternative splicing that gives rise to numerous isoforms differentially expressed in brain tissues. A thorough bioinformatic analysis of the altered transcripts was conducted for each patient. The different expression profiles of the isoforms of this gene and their influence on the excitatory–inhibitory balance in crucial brain structures could contribute to the phenotypic variability related to DLG2 alterations. Further studies on patients would be helpful to enrich clinical and neurodevelopmental findings and elucidate the molecular mechanisms subtended to NDDs.

Background. 46,XX disorders of sex development are rare. Approximately, 90% of XX males are SRY-positive, while testicular development in the absence of SRY takes place in a minority. Methods: A boy with 46,XX karyotype (SRY-negative; absence of SOX9 duplications) was investigated by targeted Next Generation Sequencing (NGS), Multiplex ligation-dependent probe amplification (MLPA), and Comparative Genomic Hybridization array (CGH-array). Results: The boy had normal male phenotype and normal prepubertal values of testicular hormones. He presented a heterozygous duplication of 49.626 bp, encompassing exons 2 and 3 of DMRT1. The result was arr[GRCh37] 9p24.3(845893_895518)x3. Since both breakpoints are harbored in the intronic regions, the duplication does not stop or shift the coding frame. Additional known pathogenic or uncertain variants in pro-testis gene cascade were not identified. Conclusions: This study report a boy with 46,XX testicular disorder of sex differentiation, showing a de novo partial intragenic duplication of DMRT1. This intragenic duplication may result in a gain of function, acting as primary pro-testis gene (or anti-ovary gene) in a 46,XX human foetus and permitting normal pre-pubertal endocrine testis function.

Multiple small supernumerary marker chromosomes (sSMCs) are among the rarest cytogenetic abnormalities as they represent roughly 1.4% of cases with sSMCs. We report on a prenatal case presenting de novo multiple sSMCs; these sSMCs were characterized by array CGH and FISH and resulted deriving from three different chromosomes: a der(13), a der(15) and a der(20). The co-presence of der(13), der(20), and der(15) have not been reported yet. The clinical consequences of this marker combination cannot be precisely predicted. However, according to the publicly available databases, the partial trisomies of chromosome 13 and 20 have probably a pathogenic effect. It is worth noting that a cooperative effect, due to interactions among genes harbored on the three derivatives, cannot be excluded, making the genetic counseling challenging.