18q Deletion Syndrome Presenting with Late-Onset Combined Immunodeficiency.

Patients with chromosome 18q deletion syndrome generally experience hypogammaglobulinemia. Herein, we describe two patients with chromosome 18q deletion syndrome who presented with late-onset combined immune deficiency (LOCID), which has not been previously reported. Patient 1 was a 29-year-old male with 18q deletion syndrome, who was being managed for severe motor and intellectual disabilities at the Yamabiko Medical Welfare Center for 26 years. Although the patient had few infections, he developed Pneumocystis pneumonia at the age of 28. Patient 2, a 48-year-old female with intellectual disability and congenital malformations, was referred to Tokyo Medical and Dental University Hospital with abnormal bilateral lung shadows detected on her chest radiography. Computed tomography showed multiple lymphadenopathies and pneumonia. A lymph node biopsy of the inguinal region revealed granulomatous lymphadenitis, and a chromosomal examination revealed 18q deletion. Array-based genomic hybridization analysis revealed deletion at 18q21.32-q22.3 for patient 1 and at 18q21.33-qter for patient 2. Immune status work-up of the two patients revealed panhypogammaglobulinemia, decreased number of memory B cells and naïve CD4+ and/or CD8+ cells, reduced response on the carboxyfluorescein diacetate succinimidyl ester T-cell division test, and low levels of T-cell receptor recombination excision circles and Ig κ-deleting recombination excision circles. Consequently, both patients were diagnosed with LOCID. Although patients with 18q deletion syndrome generally experience humoral immunodeficiency, the disease can be further complicated by cell-mediated immunodeficiency, causing combined immunodeficiency. Therefore, patients with 18q deletion syndrome should be regularly tested for cellular/humoral immunocompetence.

Nexus between genome-wide copy number variations and autism spectrum disorder in Northeast Han Chinese population.

BACKGROUND: Autism spectrum disorder (ASD) is a common neurodevelopmental disorder, with an increasing prevalence worldwide. Copy number variation (CNV), as one of genetic factors, is involved in ASD etiology. However, there exist substantial differences in terms of location and frequency of some CNVs in the general Asian population. Whole-genome studies of CNVs in Northeast Han Chinese samples are still lacking, necessitating our ongoing work to investigate the characteristics of CNVs in a Northeast Han Chinese population with clinically diagnosed ASD. METHODS: We performed a genome-wide CNVs screening in Northeast Han Chinese individuals with ASD using array-based comparative genomic hybridization. RESULTS: We found that 22 kinds of CNVs (6 deletions and 16 duplications) were potentially pathogenic. These CNVs were distributed in chromosome 1p36.33, 1p36.31, 1q42.13, 2p23.1-p22.3, 5p15.33, 5p15.33-p15.2, 7p22.3, 7p22.3-p22.2, 7q22.1-q22.2, 10q23.2-q23.31, 10q26.2-q26.3, 11p15.5, 11q25, 12p12.1-p11.23, 14q11.2, 15q13.3, 16p13.3, 16q21, 22q13.31-q13.33, and Xq12-q13.1. Additionally, we found 20 potential pathogenic genes of ASD in our population, including eight protein coding genes (six duplications [DRD4, HRAS, OPHN1, SHANK3, SLC6A3, and TSC2] and two deletions [CHRNA7 and PTEN]) and 12 microRNAs-coding genes (ten duplications [MIR202, MIR210, MIR3178, MIR339, MIR4516, MIR4717, MIR483, MIR675, MIR6821, and MIR940] and two deletions [MIR107 and MIR558]). CONCLUSION: We identified CNVs and genes implicated in ASD risks, conferring perception to further reveal ASD etiology.

The Precise Breakpoint Mapping in Paracentric Inversion 10q22.2q23.3 by Comprehensive Cytogenomic Analysis, Multicolor Banding, and Single-Copy Chromosome Sequencing.

Detection and precise genomic mapping of balanced chromosomal abnormalities in patients with impaired fertility or a clinical phenotype represent a challenge for current cytogenomics owing to difficulties with precise breakpoint localization in the regions enriched for DNA repeats and high genomic variation in such regions. Here, we present a comprehensive cytogenomic approach to breakpoint mapping in a rare paracentric inversion on 10q (in a patient with oligoasthenoteratozoospermia and necrozoospermia) that does not affect other phenotype traits. Multicolor banding, chromosomal microarray analysis, chromosome microdissection with reverse painting, and single-copy sequencing of the rearranged chromosome were performed to determine the length and position of the inverted region as well as to rule out a genetic imbalance at the breakpoints. As a result, a paracentric 19.251 Mbp inversion at 10q22.2q23.3 was described. The most probable location of the breakpoints was predicted using the hg38 assembly. The problems of genetic counseling associated with enrichment for repeats and high DNA variability of usual breakpoint regions were discussed. Possible approaches for cytogenomic assessment of couples with balanced chromosome rearrangements and problems like reproductive failures were considered and suggested as useful part of effective genetic counseling.

Prenatal sonographic and cytogenetic/molecular findings of 22q11.2 microdeletion syndrome in 48 confirmed cases in a single tertiary center.

PURPOSE: We aimed to present the fetal ultrasound, cytogenetic/molecular testing and postmortem or postnatal clinical findings of cases with 22q11.2DS diagnosed prenatally. MATERIALS AND METHODS: A retrospective medical record review of 48 prenatal cases diagnosed with 22q11.2DS were evaluated in our institution. Detailed ultrasound examination was performed on all fetuses. Postmortem and postnatal examinations were evaluated. The microdeletions were detected by karyotyping or microarray, then confirmed by FISH. Descriptive statistical analysis was performed. RESULTS: Demographic data of 48 prenatal cases including 46 singletons and 1 dichorionic diamniotic twin pregnancy were evaluated. The most common extracardiac anomaly was skeletal system anomalies (25%), in which PEV was the most frequent one (20.8%). Polyhydramnios rate was detected as 31%, in 6.6% as an isolated finding. Microdeletion has been detected by karyotyping in 13 cases (13/47, 27.7%) (including 2 unbalanced translocations), by FISH in 28 cases (28/48, 58.3%), by microarray/a-CGH testing in 7 cases. Microarray analysis showed that in one case with unbalanced translocation had two consecutive deletions; one was proximal and other one distal to critical region and not encompassing TBX1 gene but CRKL and LZTR1 genes. CONCLUSION: The current study demonstrates the whole spectrum of atypical phenotypic and genotypic variations of 22q11.2DS in the largest prenatal case series reported to date. Therefore, differential diagnosis should be considered not solely in CHD, but also in the presence of isolated clubfeet and polyhydramnios. Establishing the diagnosis in the prenatal period may allow a postnatal multidisciplinary approach, as well as affect the actual prevalence of the disease.

Prenatal Diagnosis of Small Supernumerary Marker Chromosome 10 by Array-Based Comparative Genomic Hybridization and Microdissected Chromosome Sequencing.

Interpreting the clinical significance of small supernumerary marker chromosomes (sSMCs) in prenatal diagnosis is still an urgent problem in genetic counselling regarding the fate of a pregnancy. We present a case of prenatal diagnosis of mosaic sSMC(10) in a foetus with a normal phenotype. Comprehensive cytogenomic analyses by array-based comparative genomic hybridization (aCGH), sSMC microdissection with next-generation sequencing (NGS) of microdissected library, fluorescence in situ hybridization (FISH) with locus-specific and telomere-specific DNA probes and quantitative real-time PCR revealed that sSMC(10) had a ring structure and was derived from the pericentromeric region of chromosome 10 with involvement of the 10p11.21-p11.1 and 10q11.21-q11.23 at 1.243 Mb and 7.173 Mb in size, respectively. We observed a difference in the length of sSMC(10) between NGS data of the DNA library derived from a single copy of sSMC(10), and aCGH results that may indicate instability and structural mosaicism for ring chromosomes in foetal cells. The presence of a 9 Mb euchromatin region in the analysed sSMC(10) did not lead to clinical manifestations, and a healthy girl was born at term. We suggest that the ring structure of sSMCs could influence sSMC manifestations and should be taken into account in genetic counselling during prenatal diagnosis.

[Application of Array-based Comparative Genomic Hybridization in Diagnostic Assessment of Abnormal Prenatal Serological Screening Results of Down's Syndrome].

OBJECTIVE: To explore the application of array-based comparative genomic hybridization (a-CGH) technology in the prenatal diagnostic assessment of abnormal serological prenatal screening results of Down's syndrome (DS). METHODS: A total of 3 578 amniotic fluid samples from pregnant women who underwent amniocentesis for prenatal diagnosis solely due to abnormal serological prenatal screening results were selected. The samples were categorized into 3 groups, 2 624 in the high-risk group, 662 in the borderline-risk group, and 292 in the abnormal multiple of median (MoM) group. a-CGH was performed on the Agilent CGX ™ (8×60K) platform and the data were analyzed by the Genoglyphix ® software. RESULTS: The overall detection rate of chromosomal abnormalities was 3.38% (121/3 578). Among the chromosomal abnormalities, 49.59% (60/121) was aneuploidies, 42.15% (51/121) was pathogenic copy number variants (pCNVs), and 8.26% (10/121) was likely pathogenic CNVs (lpCNVs). The detection rate of copy number variant of uncertain significance (VUS) was 1.03% (37/3 578). In the high-risk, the borderline-risk and the abnormal MoM groups, the detection rate of chromosomal abnormalities was 3.54% (93/2 624), 2.87% (19/662) and 3.08% (9/292), respectively; the detection rate of p/lp CNVs was 1.64% (43/2 624), 1.81% (12/662) and 2.05% (6/292), respectively; the detection rate of trisomy 21 and trisomy 18 was 1.37% (36/2 624), 0.76% (5/662) and 0.34% (1/292) in the three groups, respectively. There were no significant differences in all the detection rate among these groups ( P>0.05). One sample with X(51)/XYY(49) confirmed by fluorescence in situ hybridization (FISH) was misdiagnosed by a-CGH. CONCLUSION: Prenatal diagnosis with a-CGH is of great significance for reducing birth defects in pregnancies with abnormal serological prenatal screening results of DS. It can also be used to detect CNVs of microdeletion/microduplication syndromes.

[Application of Array-based Comparative Genomic Hybridization in the Prenatal Diagnosis of Fetal Chromosomal Aberration in Gravidas with Advanced Age].

OBJECTIVE: To evaluate the clinical application of array-based comparative genomic hybridization (a-CGH) in the prenatal diagnosis of fetal chromosomal aberrations in gravidas with advanced maternal age (AMA). METHODS: A total of 3 677 amniotic fluid samples from pregnant women who underwent amniocentesis for prenatal diagnosis solely due to AMA were selected. Array-CGH was performed on the Agilent CGX TM (8X60K) platform and the data were analyzed by the Genoglyphix software. RESULTS: The overall detection rate of chromosomal aberration was 2.04% (75/3677), with 53.33% (40/75) being aneuploidies, including 22 cases of trisomy-21, 5 cases of trisomy-18, 8 cases with XXY, 3 cases of XYY and 2 cases of mosaic monosomy X, 32.00% (24/75) being pathogenic copy number variations (pCNVs), including 19 cases of microdeletion and 5 cases of microduplication, with the fragment size ranging from 323 kb to 26 780 kb, and 14.67% (11/75) being likely pathogenic CNVs (lpCNVs), including 7 cases of microdeletion and 7 cases of microduplication, with the fragment size ranging from 358 kb to 16 873 kb. Besides, the detection rate of CNVs of unknown clinical significance (VUS) was 0.84% (31/3 677). The detection rate of aneuploidies increased significantly with increased maternal age ( P<0.05). However, there were no significant differences in the detection rate of p/lpCNVs among different maternal age groups ( P>0.05). CONCLUSION: Our findings suggest that, compared with traditional karyotype analysis, a-CGH not only detects aneuploidies, but also detect pathogenic CNVs, including microdeletion/microduplication syndromes. The detection rate of fetal aneuploidies was closely correlated to maternal age. However, no correlation was found between the detection rate of p/lpCNVs and maternal age.

Array-Based Comparative Genomic Hybridization Analysis in Children with Developmental Delay/Intellectual Disability.

Developmental delay (DD) is a condition wherein developmental milestones and learning skills do not occur at the expected age range for patients under 5 years of age. Intellectual disability (ID) is characterized by limited or insufficient development of mental abilities, including intellectual functioning impairments, such as learning and cause-effect relationships. Isolated and syndromic DD/ID cases show extreme genetic heterogeneity. Array-based comparative genomic hybridization aCGH) can detect copy number variations (CNVs) on the whole genome at higher resolution than conventional cytogenetic methods. The diagnostic yield of aCGH was 15.0-20.0% in DD/ID cases. The aim of this study was to discuss the clinical findings and aCGH analysis results of isolated and syndromic DD/ID cases in the context of genotype-phenotype correlation. The study included 139 cases (77 females, 62 males). Data analysis revealed 38 different CNVs in 35 cases. In this study, 19 cases with pathogenic CNVs (13.6%) and five cases with likely pathogenic CNVs (3.5%) were found in a total of 139 cases diagnosed with DD/ID. When all pathogenic and likely pathogenic cases were evaluated, the diagnosis rate was 17.1%. The use of aCGH analysis as a first-tier test in DD/ID cases contributes significantly to the diagnosis rates and enables the detection of rare microdeletion/microduplication syndromes. The clear determination of genetic etiology contributes to the literature in terms of genotype-phenotype correlation.

Integrated analysis revealing genome-wide chromosomal copy number variation in supraglottic laryngeal squamous cell carcinoma.

Laryngeal squamous cell carcinoma (LSCC) is a genetically complex tumor type and one of the leading causes of cancer-associated disability and mortality. Genetic instability, such as chromosomal instability, is associated with the tumorigenesis of LSCC. Copy number variations (CNVs) have been demonstrated to contribute to the genetic diversity of tumor pathogenesis. Comparative genomic hybridization (CGH) has emerged as a high-throughput genomic technology that facilitates the aggregation of high-resolution data of cancer-associated genomic imbalances. In the present study, a total of 38 primary supraglottic LSCC cases were analyzed by high-resolution array-based CGH (aCGH) to improve the understanding of the genetic alterations in LSCC. Additionally, integration with bioinformatic analysis of microarray expression profiling data from the Gene Expression Omnibus (GEO) database provided a fundamental method for the identification of putative target genes. Genomic CNVs were detected in all cases. The size of net genomic imbalances per case ranged between a loss of 682.3 Mb (~24% of the genome) and a gain of 1,958.6 Mb (~69% of the genome). Recurrent gains included 2pter-q22.1, 3q26.1-qter, 5pter-p12, 7p22.3p14.1, 8p12p11.22, 8q24.13q24.3, 11q13.2q13.4, 12pter-p12.2, 18pter-p11.31 and 20p13p12.1, whereas recurrent losses included 3pter-p21.32, 4q28.1-q35.2, 5q13.2-qter, 9pter-p21.3 and monosomy 13. Gains of 3q26.1-qter were associated with tumor stage, poor differentiation and smoking history. Additionally, through integration with bioinformatic analysis of data from the GEO database, putative target oncogenes, including sex-determining region Y-box 2, eukaryotic translation initiation factor 4 gamma 1, fragile X-related gene 1, disheveled segment polarity protein 3, defective n cullin neddylation 1 domain containing 1, insulin like growth factor 2 mRNA binding protein 2 and CCDC26 long non-coding RNA, and tumor suppressor genes, such as CUB and sushi multiple domains 1, cyclin dependent kinase inhibitor 2A, protocadherin 20, serine peptidase inhibitor Kazal type 5 and Nei like DNA glycosylase 3, were identified in supraglottic LSCC. Supraglottic LSCC is a genetically complex tumor type and aCGH was demonstrated to be effective in the determination of molecular profiles with higher resolution. The present results enable the identification of putative target oncogenes and tumor suppressor gene mapping in supraglottic LSCC.

Clinical Applications of Chromosomal Microarray Testing in Myeloid Malignancies.

PURPOSE OF REVIEW: Knowledge of both somatic mutations and copy number aberrations are important for the understanding of cancer pathogenesis and management of myeloid neoplasms. The currently available standard of care technologies for copy number assessment such as conventional karyotype and FISH are either limited by low resolution or restriction to targeted assessment. RECENT FINDINGS: Chromosomal microarray (CMA) is effective in characterization of chromosomal and gene aberrations of diagnostic, prognostic, and therapeutic significance at a higher resolution than conventional karyotyping. These results are complementary to NGS mutation studies. Copy-neutral loss of heterozygosity (CN-LOH), which is prognostic in AML, is currently only identified by CMA. Yet, despite the widespread availability, CMA testing is not routinely performed in diagnostic laboratories due to lack of knowledge on best-testing practices for clinical work-up of myeloid neoplasms. In this review, we provide an overview of the clinical significance of CMA in acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), and myelodysplastic/myeloproliferative neoplasms (MDS/MPN). We will also elaborate the specific clinical scenarios where CMA can provide additional information essential for management and could potentially alter treatment. Chromosomal microarray (CMA) is an effective technology for characterizing chromosomal copy number changes and copy-neutral loss of heterozygosity of diagnostic, prognostic, and therapeutic significance at a high resolution in myeloid malignancies.

Primrose syndrome associated with unclassified immunodeficiency and a novel ZBTB20 mutation.

Primrose syndrome is a congenital malformation syndrome characterized by intellectual disability, developmental delay, progressive muscle wasting, and ear lobe calcification. Mutations in the ZBTB20 gene have been established as being accountable for this syndrome. In this study, a novel de novo ZBTB20 mutation, NM_001164342.2:c.1945C>T (p.Leu649Phe), has been identified through whole exome sequencing (WES) in a female patient presenting a typical Primrose phenotype. Because the present patient exhibited recurrent otitis media, detailed immunological examinations were performed in this study and subnormal immunoglobulin levels were firstly identified in a Primrose patient. Anatomical anomaly of the inner ear has never been reported in this patient and WES data did not include any relevant variants causally linked with the immunologic defect. Thus, there is a possibility of a relation between an unclassified immunodeficiency with selective IgG2 deficiency and Primrose syndrome and this may be the reason of recurrent otitis media frequently observed in Primrose patients. Because subnormal levels of IgG2 in this patient might be caused by an unrelated and still uncharacterized genetic cause, further studies are required to prove the causal link between aberrant ZBTB20 function and immunodeficiency.

Effects of Copy Number Variations on Developmental Aspects of Children With Delayed Development.

OBJECTIVE: To determine effects of copy number variations (CNV) on developmental aspects of children suspected of having delayed development. METHODS: A retrospective chart review was done for 65 children who underwent array-comparative genomic hybridization after visiting physical medicine & rehabilitation department of outpatient clinic with delayed development as chief complaints. Children were evaluated with Denver Developmental Screening Test II (DDST-II), Sequenced Language Scale for Infants (SELSI), or Preschool Receptive-Expressive Language Scale (PRES). A Mann-Whitney U test was conducted to determine statistical differences of developmental quotient (DQ), receptive language quotient (RLQ), and expressive language quotient (ELQ) between children with CNV (CNV(+) group, n=16) and children without CNV (CNV(-) group, n=37). RESULTS: Of these subjects, the average age was 35.1 months (mean age, 35.1±24.2 months). Sixteen (30.2%) patients had copy number variations. In the CNV(+) group, 14 children underwent DDST-II. In the CNV(-) group, 29 children underwent DDSTII. Among variables, gross motor scale was significantly (p=0.038) lower in the CNV(+) group compared with the CNV(-) group. In the CNV(+) group, 5 children underwent either SELSI or PRES. In the CNV(-) group, 27 children underwent above language assessment examination. Both RLQ and ELQ were similar between the two groups. CONCLUSION: The gross motor domain in DQ was significantly lower in children with CNV compared to that in children without CNV. This result suggests that additional genetic factors contribute to this variability. Active detection of genomic imbalance could play a vital role when prominent gross motor delay is presented in children with delayed development.

Rapidly and Slowly Growing Lineages in Chromosomal Instability-Type Gland-Forming Gastric Carcinomas as Revealed by Multisampling Analysis of DNA Copy-Number Profile.

BACKGROUND: To examine whether gastric carcinoma (GC) with chromosomal instability (CIN-type GC), the largest category in the Cancer Genome Atlas classification, consists of a single genetic lineage, we conducted a multisampling analysis of genomic DNA copy-number profile. METHODS: We performed array-based comparative genomic hybridization using formalin-fixed paraffin-embedded tissues from 54 gland-forming GCs containing a total of 106 DNA samples from mucosal, extramucosal invasive, and lymph node lesions. Microarray data were analyzed by unsupervised hierarchical clustering and penetrance plots. Epstein-Barr virus infection status and mismatch repair (MMR) enzyme-silencing/p53/mucin expression were examined by in situ hybridization and immunohistochemistry, respectively. RESULTS: The samples examined were divided into gain-rich cluster A and loss-rich cluster B, which were different in tumor locus and patient age. The T1/T2-4 ratio, the frequency of small cancers (diameter ≤2-4 cm), and intestinal mucin expression were higher in cluster B than in cluster A, but there were no significant differences in the frequencies of MMR silencing, mutant p53 pattern, and lymph node metastasis between the 2 clusters. CONCLUSIONS: We demonstrated that CIN-type GC could be categorized into 2 genetic lineages which are different in terms of rapidity of local extension but similar in terms of nodal metastasis risk.

Progression Potential of Ductal Carcinoma in situ Assessed by Genomic Copy Number Profiling.

BACKGROUND: Ductal carcinoma in situ (DCIS) of the breast is heterogeneous in terms of the risk of progression to invasive ductal carcinoma (IDC). To treat DCIS appropriately for its progression risk, we classified individual DCIS by its profile of genomic changes into 2 groups and correlated them with clinicopathological progression factors. METHODS: We used surgically resected, formalin-fixed, paraffin-embedded tissues of 22 DCIS and 30 IDC lesions. We performed immunohistochemical intrinsic subtyping, array-based comparative genomic hybridization, and unsupervised clustering. RESULTS: The samples were divided into 2 major clusters, A and B. Cluster A showed a greater number of gene and chromosome copy number alterations, a larger IDC/DCIS ratio, a higher frequency of nonluminal subtype, a lower frequency of luminal subtype, and a higher nuclear grade, when compared with cluster B. However, there was no difference in the frequencies of lymph node metastasis between clusters A and B. We identified 9 breast-cancer-related genes, including TP53 and GATA3, that highly contributed to the discrimination of A and B clusters. CONCLUSION: Classification of breast tumors into rapidly progressive cluster A and the other (cluster B) may contribute to select the treatment appropriate for their progression risk.

Identification of ATP7B gene variant by combined use of Sanger sequencing, array CGH and quantitative PCR / 中华医学遗传学杂志

Objective@#To identify the type and origin of ATP7B gene mutation in a family affected with Wilson disease by combined use of multiple methods.@*Methods@#Peripheral blood samples were collected from the proband, her parents and her brother. Sanger sequencing were used to detect point mutation and small deletion/insertion of the 21 exons and flanking sequences of the ATP7B gene in all family members. Array-based comparative genomic hybridization (aCGH) was performed to identify copy number variations (CNVs) of the ATP7B gene in the proband. The result was validated by quantitative PCR (qPCR) in other 3 members.@*Results@#Sanger sequencing indicated that the proband carried a heterozygous variation c. 2668G>A (p.V890M) derived from her mother. In addition, 5 common SNPs were detected in her mother, three of which were also identified in her father and brother. The 5 SNPs in the proband were of the wide type. aCGH analysis demonstrated that the proband was heterozygous for a 4 kb deletion, which encompassed exons 2 and 3 of the ATP7B gene and 2 SNPs. qPCR showed that the copy number in her father and brother was about half of the control, indicating heterozygous loss of exons 2 and 3.@*Conclusion@#The combined Sanger sequencing, array CGH and qPCR has identified a novel CNV involving the ATP7B gene. The strategy can improve the diagnostic rate for hereditary or rare diseases.

Effects of Copy Number Variations on Developmental Aspects of Children With Delayed Development

OBJECTIVE: To determine effects of copy number variations (CNV) on developmental aspects of children suspected of having delayed development. METHODS: A retrospective chart review was done for 65 children who underwent array-comparative genomic hybridization after visiting physical medicine & rehabilitation department of outpatient clinic with delayed development as chief complaints. Children were evaluated with Denver Developmental Screening Test II (DDST-II), Sequenced Language Scale for Infants (SELSI), or Preschool Receptive-Expressive Language Scale (PRES). A Mann-Whitney U test was conducted to determine statistical differences of developmental quotient (DQ), receptive language quotient (RLQ), and expressive language quotient (ELQ) between children with CNV (CNV(+) group, n=16) and children without CNV (CNV(–) group, n=37). RESULTS: Of these subjects, the average age was 35.1 months (mean age, 35.1±24.2 months). Sixteen (30.2%) patients had copy number variations. In the CNV(+) group, 14 children underwent DDST-II. In the CNV(–) group, 29 children underwent DDST-II. Among variables, gross motor scale was significantly (p=0.038) lower in the CNV(+) group compared with the CNV(–) group. In the CNV(+) group, 5 children underwent either SELSI or PRES. In the CNV(–) group, 27 children underwent above language assessment examination. Both RLQ and ELQ were similar between the two groups. CONCLUSION: The gross motor domain in DQ was significantly lower in children with CNV compared to that in children without CNV. This result suggests that additional genetic factors contribute to this variability. Active detection of genomic imbalance could play a vital role when prominent gross motor delay is presented in children with delayed development.

A Novel Acquired t(2;4)(q36.1;q24) with a Concurrent Submicroscopic del(4)(q23q24) in An Adult with Polycythemia Vera.

Background: Polycythemia vera (PV) is a clonal myeloid stem cell disease characterized by a growth-factor independent erythroid proliferation with an inherent tendency to transform into overt acute myeloid malignancy. Approximately 95% of the PV patients harbor the JAK2V617F mutation while less than 35% of the patients harbor cytogenetic abnormalities at the time of diagnosis. Methods and Results: Here we present a JAK2V617F positive PV patient where G-banding revealed an apparently balanced t(2;4)(q35;q21), which was confirmed by 24-color karyotyping. Oligonucleotide array-based Comparative Genomic Hybridization (aCGH) analysis revealed an interstitial 5.4 Mb large deletion at 4q23q24. Locus-specific fluorescent in situ hybridization (FISH) analyses confirmed the mono-allelic 4q deletion and that it was located on der(4)t(2;4). Additional locus-specific bacterial artificial chromosome (BAC) probes and mBanding refined the breakpoint on chromosome 2. With these methods the karyotype was revised to 46,XX,t(2;4)(q36.1;q24)[18]/46,XX[7]. Conclusions: This is the first report on a PV patient associated with an acquired novel t(2;4)(q36.1;q24) and a concurrent submicroscopic deletion del(4)(q23q24). The study also underscores the benefit of combined usage of FISH and oligo-based aCGH analysis in characterizing chromosomal abnormalities. The present findings provide additional clues to unravel important molecular pathways in PV to obtain the full spectrum of acquired chromosomal and genomic aberrations, which eventually may improve treatment options.

Genetic Alterations in Essential Thrombocythemia Progression to Acute Myeloid Leukemia: A Case Series and Review of the Literature.

The genetic events associated with transformation of myeloproliferative neoplasms (MPNs) to secondary acute myeloid leukemia (sAML), particularly in the subgroup of essential thrombocythemia (ET) patients, remain incompletely understood. Deep studies using high-throughput methods might lead to a better understanding of genetic landscape of ET patients who transformed to sAML. We performed array-based comparative genomic hybridization (aCGH) and whole exome sequencing (WES) to analyze paired samples from ET and sAML phases. We investigated five patients with previous history of MPN, which four had initial diagnosis of ET (one case harboring JAK2 p.Val617Phe and the remaining three CALR type II p.Lys385fs*47), and one was diagnosed with MPN/myelodysplastic syndrome with thrombocytosis (SF3B1 p.Lys700Glu). All were homogeneously treated with hydroxyurea, but subsequently transformed to sAML (mean time of 6 years/median of 4 years to transformation). Two of them have chromosomal abnormalities, and both acquire 2p gain and 5q deletion at sAML stage. The molecular mechanisms associated with leukemic progression in MPN patients are not clear. Our WES data showed TP53 alterations recurrently observed as mutations (missense and frameshift) and monoallelic loss. On the other hand, aCGH showed novel chromosome abnormalities (+2p and del5q) potentially associated with disease progression. The results reported here add valuable information to the still fragmented molecular basis of ET to sAML evolution. Further studies are necessary to identify minimal deleted/amplified region and genes relevant to sAML transformation.

Recurrent Copy Number Variants Associated with Syndromic Short Stature of Unknown Cause.

BACKGROUND/AIMS: Genetic imbalances are responsible for many cases of short stature of unknown etiology. This study aims to identify recurrent pathogenic copy number variants (CNVs) in patients with syndromic short stature of unknown cause. METHODS: We selected 229 children with short stature and dysmorphic features, developmental delay, and/or intellectual disability, but without a recognized syndrome. All patients were evaluated by chromosomal microarray (array-based comparative genomic hybridization/single nucleotide polymorphism array). Additionally, we searched databases and previous studies to recover recurrent pathogenic CNVs associated with short stature. RESULTS: We identified 32 pathogenic/probably pathogenic CNVs in 229 patients. By reviewing the literature, we selected 4 previous studies which evaluated CNVs in cohorts of patients with short stature. Taken together, there were 671 patients with short stature of unknown cause evaluated by chromosomal microarray. Pathogenic/probably pathogenic CNVs were identified in 87 patients (13%). Seven recurrent CNVs, 22q11.21, 15q26, 1p36.33, Xp22.33, 17p13.3, 1q21.1, 2q24.2, were observed. They are responsible for about 40% of all pathogenic/probably pathogenic genomic imbalances found in short stature patients of unknown cause. CONCLUSION: CNVs seem to play a significant role in patients with short stature. Chromosomal microarray should be used as a diagnostic tool for evaluation of growth disorders, especially for syndromic short stature of unknown cause.