22q11 Microdeletion Research Articles

Recurrent 17q12 microduplications contribute to renal disease but not diabetes

Background17q12 microdeletion and microduplication syndromes present as overlapping, multisystem disorders. We assessed the disease phenotypes of individuals with 17q12 CNV in a population-based cohort.MethodsWe investigated 17q12 CNV using microarray data...

Tetralogy of Fallot in the fetus - from diagnosis to delivery. 18-year experience of a tertiary Fetal Cardiology Center.

Tetralogy of Fallot (TOF) is a common congenital heart disease but very heterogeneous in terms of detailed cardiac anatomy, associated malformations, and genetic anomalies, especially when assessed prenatally. We aimed to analyze the clinical spectrum of TOF in the prenatal period, including detailed cardiac morphology, coexisting anomalies, and their impact on short-term neonatal outcome. We also assessed changing trends in the prenatal diagnostic workup of TOF. A retrospective cohort study including fetuses diagnosed with TOF between 2002 and 2019 was conducted in a tertiary Fetal Cardiology Center. Medical records and echocardiographic examinations were reviewed to collect demographic, sonographic, and genetic data. Among 326 TOF fetuses, 237 (73%) had pulmonary stenosis (TOF-PS), 72 (22%) pulmonary atresia (TOF-PA), and 17 (5%) absent pulmonary valve (TOF-APV). The yearly number of diagnoses increased during the study period, with decreasing fetal age at the time of diagnosis. Extracardiac malformations were found in 172 (53%) fetuses, cardiovascular malformations in 159 (49%), and genetic anomalies in 99 (39% of the tested group). Hypoplastic thymus, right aortic arch, and polyhydramnios were sonographic markers of microdeletion 22q11. Left-to-right ductal flow was predictive of postnatal ductal dependency. The perinatal outcome was dependent on the presence of associated anomalies and disease subtype, with TOF-APV having the worst prognosis. Extracardiac and genetic anomalies are common in fetuses with TOF, and, together with disease subtype and ductal flow assessment, they impact the perinatal management and outcomes. Genetic testing with array comparative genomic hybridization should be offered in all cases.

Molecular diagnosis of cytogenetic abnormalities in patients with schizophrenia

IntroductionSchizophrenia is a severe and chronic disorder causing significant disability and functional decline. Schizophrenia is a polygenic disease, with about 100 monogenic sites and 11 sites of chromosomal deletions / duplications involved in its pathogenesis identified. It is a pleiotropic disease, with causative genetic changes leading to multiple symptoms, including bipolar disorder, autism spectrum disorders, ADHD, mental retardation and epilepsy. The chromosomal microarray (CMA) technology detects submicroscopic chromosomal changes, which are involved in neurodevelopmental disorders, and are subject to prenatal diagnosis. Pathological findings in CMA are detected in 10-20% of patients with neurodevelopmental disorders and can contribute significantly to medical follow-up, prognosis assessment, influence treatment choice, and allow prenatal diagnosis. Preliminary studies in schizophrenia identified pathological CMA findings in 10–30% of patients.ObjectivesCMA testing of schizophrenia patients to detect genetic changes causing the disease.MethodsRecruitment of schizophrenia patients from the Haifa and Western Galilee districts of Clalit, genetic counseling in Carmel Hospital, CMA testing of the consenting patients.ResultsSchizophrenia patients with and without neurodevelopmental disorders underwent CMA analysis, with the findings of significant chromosomal submicroscopic disorders (such as 22q11 microdeletion, among others) in 30% of the patients, providing the explanation for the patients’ symptoms and enabling specific medical follow-up and adjusted pharmacological treatment.ConclusionsCMA can be used in diagnosing schizophrenia, assessing prognosis, adjusting pharmacological treatment and follow-up and providing genetic counseling including prenatal diagnosis, as in cases neurodevelopmental disorders. The findings support the application of CMA as part of a routine procedures in schizophrenia.DisclosureNo significant relationships.

Airway Characteristics of Patients With 22q11 Deletion Undergoing Pulmonary Artery Reconstruction Surgery: Retrospective Cohort Study.

We have previously shown that patients with a chromosome 22q11 microdeletion are at risk for prolonged respiratory failure after pulmonary artery reconstruction surgery compared with those with normal genotype. We sought to describe preexisting airway abnormalities in this patient population and examine relationships between airway abnormalities and outcomes. Single-center retrospective chart review from Society of Thoracic Surgery and Pediatric Cardiac Critical Care Consortium databases and the electronic medical record. Lucile Packard Children's Hospital at Stanford from September 2017 to February 2019. All patients undergoing pulmonary artery reconstruction surgery were considered for inclusion. We identified 127 patients meeting study inclusion criteria. Thirty-nine patients met specific criteria and underwent screening preoperative bronchoscopy including microdirect laryngoscopy and lower airway examination. Postoperative bronchoscopy was performed at the discretion of the intensive care team. Airway abnormalities were detected in 25/26 of children (96%) with a chromosome 22q11 deletion who underwent preoperative bronchoscopy. Upper and lower airway pathologies were found in 19/25 (73%) and 21/25 (81%) patients, respectively, and it was common for patients to have more than one abnormality. Presence of 22q11 deletion was associated with longer duration of mechanical ventilation (9.1 vs 4.3 d; p = 0.001), use of noninvasive positive pressure support (13 vs 6 d; p = 0.001), and longer hospital stays (30 vs 14 d; p = 0.002). These outcomes were worse when compared with patients with known airway abnormalities who did not have 22q11 deletion. Preexisting upper and lower airway pathologies are common in patients with a chromosome 22q11 deletion who undergo pulmonary artery reconstruction surgery. Despite similar postoperative hemodynamics and outcomes as their counterparts without 22q11 deletion, 22q11 deletion is associated with more postoperative respiratory complications not entirely explained by preexisting airway abnormalities.

Downregulation of miR-185 is a common pathogenic event in 22q11.2 deletion syndrome-related and idiopathic schizophrenia.

Schizophrenia (SCZ) is known as a complicated mental disease with an unknown etiology. The microdeletion of 22q11.2 is the most potent genetic risk factor. Researchers are still trying to find which genes in the deletion region are linked to SCZ. MIR185, encoding microRNA (miR)-185, is present in the minimal 1.5 megabase deletion. Nonetheless, the miR-185 expression profile and its corresponding target genes in animal models and patients with 22q11.2 deletion syndrome (22q11.2DS) imply that more study is required about miR-185 and its corresponding downstream pathways within idiopathic SCZ. The expression of hsa-miR-185-5p and its corresponding target gene, shisa family member 7 (SHISA7), sometimes called CKAMP59, were evaluated in the peripheral blood (PB) samples of Iranian Azeri patients with idiopathic SCZ and healthy subjects, matched by gender and age as control groups by quantitative polymerase chain reaction (qPCR). Fifty SCZ patients (male/female: 22/28, age (mean ± standard deviation (SD)): 35.9 ± 5.6) and 50 matched healthy controls (male/female: 23/27, age (mean ± SD): 34.7 ± 5.4) were enrolled. The expression of hsa-miR-185-5p in the PB samples from subjects with idiopathic SCZ was substantially lower than in that of control groups (posterior beta = -0.985, adjusted P-value < 0.0001). There was also a difference within the expression profile between female and male subgroups (posterior beta = -0.86, adjusted P-value = 0.046 and posterior beta = -1.015, adjusted P-value = 0.004, in turn). Nevertheless, no significant difference was present in the expression level of CKAMP59 between PB samples from patients and control groups (adjusted P-value > 0.999). The analysis of the receiver operating characteristic (ROC) curve suggested that hsa-miR-185-5p may correctly distinguish subjects with idiopathic SCZ from healthy people (the area under curve (AUC) value: 0.722). Furthermore, there was a strong positive correlation between the expression pattern of the abovementioned genes in patients with SCZ and healthy subjects (r = 0.870, P < 0.001 and r = 0.812, P < 0.001, respectively), indicating that this miR works as an enhancer. More research is needed to determine if the hsa-miR-185-5p has an enhancer activity. In summary, this is the first research to highlight the expression of the miR-185 and CKAMP59 genes in the PB from subjects with idiopathic SCZ. Our findings suggest that gene expression alterations mediated by miR-185 may play a role in the pathogenesis of idiopathic and 22q11.2DS SCZ. It is worth noting that, despite a substantial and clear relationship between CKAMP59 and hsa-miR-185-5p, indicating an interactive network, their involvement in the development of SCZ should be reconsidered based on the whole blood sample since the changed expression level of CKAMP59 was not significant. Further research with greater sample sizes and particular leukocyte subsets can greatly make these results stronger.

Prenatal ultrasound features and genetic analysis for 17q12 microdeletion syndrome.

The 17q12 microdeletion syndrome is a type of syndrome caused by a deletion of 1.4 to 1.8 Mb in the 17q12 region of the chromosome. The main clinical features of the syndrome are structural or functional abnormalities in the kidney and urethra, type 5 diabetes, and neurodevelopmental or neuropsychiatric disorders. The diverse range of phenotypes associated with 17q12 microdeletion limited clinical recognition and diagnosis. In addition, the phenotypic description of this microdeletion is mainly about postpartum. Due to the rarity of the 17q12 microdeletion itself, studies on the prenatal phenotype of the 17q12 microdeletion are limited. This study aims to analyze the prenatal ultrasound features of 17q12 microdeletion, and to investigate the possibility of genotype-phenotype relationship for providing evidence for genetic counseling in such pregnancies. A total of 3 320 pregnant women and their fetuses were collected for the detection of chromosome copy number variation sequencing (CNV-Seq) due to different ultrasound anomalies in Xiangya Hospital of Central South University. The clinical data of pregnant women and their fetuses who were found to harbor 17q12 microdeletion were reviewed, including maternal age, fetus ultrasound findings, gestational week of the invasive procedure, CNV-Seq results, and the pregnancy outcome. CNV-Seq was tested in the parents to verify whether the abnormality was de novo or inherited. The prenatal ultrasound features and CNV-Seq test results of these 12 fetuses were analyzed and their pregnancy outcomes were followed up. Approximately 0.36% (12/3 320) of fetuses were detected to have 17q12 microdeletion, all characterized as renal abnormalities, accounting for 4.2% (12/288) of all prenatal ultrasound with renal abnormalities, accounting for 48% (12/25) of prenatal ultrasound with renal abnormalities and pathogenic chromosomal abnormalities. The sizes of 17q12 deletion ranged from 1.4 to 1.7 Mb, and all of them included the HNF1B gene. Nine cases were de novo, 2 inherited from the mother, and 1 inherited from father. Among 12 fetuses with 17q12 deletion, 11 cases of prenatal ultrasound suggested bilateral hyperechogenic kidneys and 1 case only showed renal cyst, in which 3 fetuses with enlarged kidneys, 1 with clubfeet, and 1 with subependymal cyst. Pregnancy outcomes were available for 11 of the 12 fetuses. Of them, the parents of 9 fetuses with de novo deletion chose to terminate the pregnancy, and 2 live birth babies inherited from their mother with normal renal function had persistent renal echogenicity enhancement after birth. Bilateral hyperechogenic kidneys show strikingly correlation with 17q12 microdeletion, suggesting the necessity of chromosome copy numbers detection for fetuses with hyperechogenic kidneys.

Molecular and phenotypic characteristics of 15q24 microdeletion in pediatric patients with developmental disorders

Chromosome 15q24 microdeletion is a rare genetic disorder characterized by development delay, facial dysmorphism, congenital malformations, and occasional autism spectrum disorder (ASD). In this study, we identified five cases of 15q24 microdeletion using multiplex ligation-dependent probe amplification (MLPA) technology in a cohort of patients with developmental delay and/or intellectual disability. Two of these five cases had deletions that overlapped with the previously defined 1.1 Mb region observed in most reported cases. Two cases had smaller deletions (< 0.57 Mb) in the 15q24.1 low copy repeat (LCR) B-C region. They presented significant neurobehavioral features, suggesting that this smaller interval is critical for core phenotypes of 15q24 microdeletion syndrome. One case had minimal homozygous deletion of less than 0.11 Mb in the 15q24.1 LCR B-C region, which contained CYP1A1 (cytochrome P450 family 1 subfamily A member 1) and EDC3 (enhancer of mRNA decapping 3) genes, resulting in poor immunity, severe laryngeal stridor, and lower limbs swelling. This study provides additional evidence of 15q24 microdeletion syndrome with genetic and clinical findings. The results will be of significance to pediatricians in their daily practice.

Improving renal phenotype and evolving extra-renal features of 17q12 deletion encompassing the HNF1B gene.

BackgroundHNF1B deletion/intragenic mutations are the most commonly identified genetic cause of congenital anomalies of the kidney and urinary tract (CAKUT) suggested by fetal ultrasound findings such as: parenchymal hyperechogenicity, overt cystic changes or gross morphological urinary system (UT) abnormalities. The postnatal evolution of these 17q12 deletions encompassing the HNF1B gene-associated findings has not been assessed in depth.MethodsIn this observational study, we present postnatal follow-up findings in 5 of 6 cases (one pregnancy was terminated on parental request) of fetal-onset cystic/hyperechogenic kidneys eventually diagnosed with 17q12 microdeletion encompassing the HNF1B gene between 2009 and 2017.ResultsComplete normalization of kidney parenchymal abnormalities and of depressed neonatal renal function was observed in 4/5 and 5/5 patients within 2–4.9 years and 1.5–8 months, respectively. All 5 patients had preserved normal renal function at 3–11 years of follow-up. The evolving later-onset renal features included: hypomagnesemia, hyperuricemia, urinary tract infection (UTI), and bilateral grade 3–4 vesicoureteral reflux and bladder diverticula in 3, 3, 2, and 1 patient, respectively. HNF1B gene deletion-associated extra-renal manifestations with delayed presentation were global developmental delay/autistic spectrum disorder (ASD), rolandic-type seizures, overweight, and borderline fasting hyperglycemia observed in 1–2 patients each. Family history was positive for small-size or asymptomatic cystic kidneys with normal function, diabetes mellitus, seizures, and mental/psychiatric problems in 3/6 cases.ConclusionsFetal-onset HNF1B deletion-associated kidneys’ parenchymal abnormalities confirmed postnatally with initially depressed renal function might undergo complete resolution within several years and few months, respectively. However, later-onset urinary tract, metabolic, and neurodevelopmental features of this mutation might appear over years. Therefore, genetic molecular evaluation/diagnosis and continuous follow-up for evolving features are mandatory in affected children.

A Comprehensive Analysis of Cerebellar Volumes in the 22q11.2 Deletion Syndrome

BackgroundThe presence of a 22q11.2 microdeletion (22q11.2 deletion syndrome [22q11DS]) ranks among the greatest known genetic risk factors for the development of psychotic disorders. There is emerging evidence that the cerebellum is important in the pathophysiology of psychosis. However, there is currently limited information on cerebellar neuroanatomy in 22q11DS specifically. MethodsHigh-resolution 3T magnetic resonance imaging was acquired in 79 individuals with 22q11DS and 70 typically developing control subjects (N = 149). Lobar and lobule-level cerebellar volumes were estimated using validated automated segmentation algorithms, and subsequently group differences were compared. Hierarchical clustering, principal component analysis, and graph theoretical models were used to explore intercerebellar relationships. Cerebrocerebellar structural connectivity with cortical thickness was examined via linear regression models. ResultsIndividuals with 22q11DS had, on average, 17.3% smaller total cerebellar volumes relative to typically developing subjects (p < .0001). The lobules of the superior posterior cerebellum (e.g., VII and VIII) were particularly affected in 22q11DS. However, all cerebellar lobules were significantly smaller, even after adjusting for total brain volumes (all cerebellar lobules p < .0002). The superior posterior lobule was disproportionately associated with cortical thickness in the frontal lobes and cingulate cortex, brain regions known be affected in 22q11DS. Exploratory analyses suggested that the superior posterior lobule, particularly Crus I, may be associated with psychotic symptoms in 22q11DS. ConclusionsThe cerebellum is a critical but understudied component of the 22q11DS neuroendophenotype.

Translatable pathways classification (TransPath-C) for inferring processes germane to human biology from animal studies data: example application in neurobiology.

How to translate insights gained from studies in one organismal species for what is most likely to be germane in another species, such as from mice to humans, is a ubiquitous challenge in basic biology as well as biomedicine. This is an especially difficult problem when there are few molecular features that are obviously important in both species for a given phenotype of interest. Neuropathologies are a prominent realm of this complication. Schizophrenia is complex psychiatric disorder that affects 1% of the population. Many genetic factors have been proposed to drive the development of schizophrenia, and the 22q11 microdeletion (MD) syndrome has been shown to dramatically increase this risk. Due to heterogeneity of presentation of symptoms, diagnosis and formulation of treatment options for patients can often be delayed, and there is an urgent need for novel therapeutics directed toward the treatment of schizophrenia. Here, we present a novel computational approach, Translational Pathways Classification (TransPath-C), that can be used to identify shared pathway dysregulation between mouse models and human schizophrenia cohorts. This method uses variation of pathway activation in the mouse model to predict both mouse and human disease phenotype. Analysis of shared dysregulated pathways called out by both the mouse and human classifiers of TransPath-C can identify pathways that can be targeted in both preclinical and human cohorts of schizophrenia. In application to the 22q11 MD mouse model, our findings suggest that PAR1 pathway activation found upregulated in this mouse phenotype is germane for the corresponding human schizophrenia cohort such that inhibition of PAR1 may offer a novel therapeutic target.

Taiwanese Clinical Experience with Noninvasive Prenatal Testing for DiGeorge Syndrome

Objective: DiGeorge syndrome (DGS) is associated with microdeletions of chromosome 22q11. It is the second most common cause of congenital heart disease and is an important consideration whenever a conotruncal cardiac anomaly is identified. The availability of noninvasive prenatal testing (NIPT) is altering the practice of prenatal genetics and maternal-fetal medicine, resulting in a decline in invasive testing. Antenatal ultrasound and other biomarkers have their own limitation. NIPT was proposed to screen DGS with cell-free DNA in Taiwan. Here, we present our experience of prenatal diagnosis of DGS in our center. Methods: This was a retrospective study between November 1, 2019, and August 31, 2020, in Taiwan. Data were collected from 7,826 pregnant women self-referred for DGS screening with massive parallel shotgun sequencing-based NIPT. High-risk cases subsequently received amniocentesis for array comparative genomic hybridization (aCGH) to confirm the diagnosis. Characteristics of pregnancies were documented when participants received the test. Report of NIPT was completed 2 weeks after the test. Follow-up on high-risk cases was completed by telephone interview on January 30, 2021. Results: Thirteen cases showed high risk by NIPT, and 7 cases were confirmed by aCGH. The sensitivity and specificity were 100% (95% confidence interval [CI] 64.57–100.00%) and 99.92% (95% CI 99.83–99.96%). The prevalence of DGS was 1 in 1,118 pregnancies. The positive predictive rate was 53.85% (95% CI 29.14–76.79%). One true positive (TP) showed US anomaly, and 5 TPs selected termination. Discussion/Conclusion: NIPT demonstrated good performance in DGS screening. Detection of 22q11.2 deletion could be combined with routine screening to facilitate proper intervention.

Prenatal ultrasonic characteristics and genetic analysis of fetuses with chromosome 22q11 microdeletion syndrome

To analyze the prenatal ultrasonic characteristics and genetic features of 14 fetuses with chromosome 22q11 microdeletion syndrome (22q11DS). 4989 fetuses were analyzed by using single nucleotide polymorphism array (SNP array) in the Fujian Maternal and Child Health Hospital from November 2016 to November 2019. SNP array showed that 11 fetuses had classic 3 Mb microdeletion in 22q11 region, one fetus had 2.0 Mb microdeletion, and two fetuses had 1.0 Mb microdeletion. The 1.0 Mb microdeletion in 22q11 region contains SNAP29 and CRKL genes, which may increase the risk of congenital renal malformation and cardiovascular malformation. Prenatal ultrasonic characteristics of fetuses with 22q11 microdeletion syndrome vary, and SNP array is a powerful tool to diagnose such diseases, which can provide accurate genetic diagnosis and enable prenatal diagnosis.

Long-term evolution of aortic arch interruption repair with pulmonary artery autograft

Surgical correction of the aortic arch interruption (IAA) is regularly complicated by anastomosis stenosis or the long-term occurrence of arterial hypertension. In order to prevent these complications, a new surgical technique has been developed in our center consisting of the interposition of a segment of the main pulmonary artery to enlarge the aortic anastomosis. The purpose of this study was to assess the 10 years outcome of this intervention. Four children undergoing this surgery with a follow-up over 10 years were retrospectively included. Data collected focused on the last measure of blood pressure (BP), the last echocardiographic evaluation, and the aortic arch dimension on the last CT. The whole patients had IAA type B and 22q11 microdeletion. The median follow-up duration was 13.9 years (range: 9.3 to 15.3). None of them had a new surgery of the aortic arch, but one need enlargement of ascending aorta. Only one patient developed a mild restenosis at the isthmic insertion of the pulmonary autograft [Z score −2.7 at CT ( Fig. 1 C)], responsible of mild arterial hypertension (systolic BP 75th percentile, diastolic BP 98th percentile), and a left ventricle hypertrophy (Z score IVSd 2.5, Z Score LVPWd 2.1). The three others patients displayed normal BP, no left ventricular hypertrophy, no significant aortic arch obstruction on Doppler evaluation and minimum Z score of aortic arch at CT from −1.8 to −0.4 ( Fig. 1 A, B, D). None of them did experience a main pulmonary artery stenosis. Reconstruction of the aortic arch with a pulmonary artery autograft for the correction of IAA provides a good long-term result.

Prenatal diagnosis, associated findings and postnatal outcome of fetuses with truncus arteriosus communis (TAC).

To assess the spectrum of associated anomalies, the intrauterine course, postnatal outcome and management of fetuses with truncus arteriosus communis (TAC) METHODS: All cases of TAC diagnosed prenatally over a period of 8years were retrospectively collected in two tertiary referral centers. All additional prenatal findings were assessed and correlated with the outcome. The accuracy of prenatal diagnosis was assessed. 39 cases of TAC were diagnosed prenatally. Mean gestational age at first diagnosis was 22weeks (range, 13-38). Two cases were lost follow-up. Correct prenatal diagnosis of TAC was made in 21 of 24 (87.5%) cases and of TAC subtype in 19 of 21 (90.5%) cases. Prenatal diagnosis of TAC was incorrect in three cases: one newborn had aortic atresia with ventricular septal defect postnatally, one had hypoplastic right ventricle with dextro Transposition of the Great Arteries with coartation of the aorta and a third newborn had Tetralogy of Fallot with abnormal origin of the left pulmonary artery arising from the ascending aorta postnatally. These three cases were excluded from further analysis. In 9 of 34 (26.5%) cases, TAC was an isolated finding. 13 (38.2%) fetuses had additional chromosomal anomalies. Among them, microdeletion 22q11.2 was most common with a prevalence of 17.6% in our cohort. Another 3 fetuses were highly suspicious for non-chromosomal genetic syndromes due to their additional extra-cardiac anomalies, but molecular diagnosis could not be provided. Major cardiac and extra-cardiac anomalies occurred in 3 (8.8%) and in 20 (58.8%) cases, respectively. Predominantly, extra-cardiac anomalies occurred in association with chromosomal anomalies. Additionally, severe IUGR occurred in 6 (17.6%) cases. There were 14 terminations of pregnancy (41.2%), 1 (2.9%) intrauterine fetal death, 5 postnatal deaths (14.7%) and 14 (41.2%) infants were alive at last follow-up. Intention-to-treat survival rate was 70%. Mean follow-up among survivors was 42months (range, 6-104). Postoperative health status among survivors was excellent in 11 (78.6%) infants, but 5 (46.2%) of them needed repeated re-interventions due to recurrent pulmonary artery or conduit stenosis. The other 3 (21.4%) survivors were significantly impaired due to non-cardiac problems. TAC is a rare and complex cardiac anomaly that can be diagnosed prenatally with high precision. TAC is frequently associated with chromosomal and extra-cardiac anomalies, leading to a high intrauterine and postnatal loss rate due to terminations and perioperative mortality. Without severe extra-cardiac anomalies, postoperative short- and medium-term health status is excellent, independent of the subtype of TAC, but the prevalence of repeated interventions due to recurrent stenosis is high.

Loss of cGMP-dependent protein kinase II alters ultrasonic vocalizations in mice, a model for speech impairment in human microdeletion 4q21 syndrome

Chromosome 4q21 microdeletion leads to a human syndrome that exhibits restricted growth, facial dysmorphisms, mental retardation, and absent or delayed speech. One of the key genes in the affected region of the chromosome is PRKG2, which encodes cGMP-dependent protein kinase II (cGKII). Mice lacking cGKII exhibit restricted growth and deficits in learning and memory, as seen in the human syndrome. However, vocalization impairments in these mice have not been determined. The molecular pathway underlying vocalization impairment in humans is not fully understood. Here, we employed cGKII knockout (KO) mice as a model for the human microdeletion syndrome to test whether vocalizations are affected by loss of the PRKG2 gene. Mice emit ultrasonic vocalizations (USVs) to communicate in social situations, stress, and isolation. We thus recorded ultrasonic vocalizations as a model for human speech. We isolated postnatal day 5–7 pups from the nest to record and analyze USVs and found significant differences in vocalizations of KO mice relative to wild-type and heterozygous mutant mice. KO mice produced fewer calls that were shorter duration and higher frequency. Because neuronal activation in the arcuate nucleus in the hypothalamus is important for the production of animal USVs following isolation from the nest, we assessed neuronal activity in the arcuate nucleus of KO pups following isolation. We found significant reduction of neuronal activation in cGKII KO pups after isolation. Taken together, our studies indicate that cGKII is important for neuronal activation in the arcuate nucleus, which significantly contributes to the production of USVs in neonatal mice. We further suggest cGKII KO mice can be a valuable animal model to investigate pathophysiology of human microdeletion 4q21 syndrome

Prenatal diagnosis, associated findings and postnatal outcome of fetuses with truncus arteriosus communis (TAC)

PurposeTo assess the spectrum of associated anomalies, the intrauterine course, postnatal outcome and management of fetuses with truncus arteriosus communis (TAC)MethodsAll cases of TAC diagnosed prenatally over a period of 8 years were retrospectively collected in two tertiary referral centers. All additional prenatal findings were assessed and correlated with the outcome. The accuracy of prenatal diagnosis was assessed.ResultsThirty nine cases of TAC were diagnosed prenatally. Mean gestational age at first diagnosis was 22 weeks (range 13–38). Two cases were lost follow-up. Correct prenatal diagnosis of TAC was made in 87.5% and of TAC subtype in 90.5%. Prenatal diagnosis was incorrect in three cases: one newborn had aortic atresia with ventricular septal defect (VSD) postnatally, one had hypo-plastic right ventricle with dextro transposition of the great arteries (d-TGA) with coarctation of the aorta and a third newborn had tetralogy of fallot (TOF) with abnormal origin of the left pulmonary artery arising from the ascending aorta postnatally. These 3 cases were excluded from further analysis.In 26.5% of cases, TAC was an isolated finding. 38.2% of fetuses had additional chromosomal anomalies. Among them, microdeletion 22q11.2 was most common with a prevalence of 17.6% in our cohort. Another 3 fetuses were highly suspicious for non-chromosomal genetic syndromes due to their additional extra-cardiac anomalies, but molecular diagnosis could not be provided. Major cardiac and extra-cardiac anomalies occurred in between 8.8% and 58.8%, respectively. Predominantly, extra-cardiac anomalies occurred in association with chromosomal anomalies. Additionally, severe IUGR occurred in 17.6%.There were 14 terminations of pregnancy (41.2%), 1 (2.9%) intrauterine fetal death, 5 postnatal deaths (14.7%) and 14 (41.2%) infants were alive at last follow-up. Intention-to-treat survival rate was 70%. Mean follow-up among survivors was 42 months (range 6–104). Postoperative health status among survivors was excellent in 78.6%, but 46.2% needed repeated re-interventions due to recurrent pulmonary artery or conduit stenosis. The other 21.4% of survivors were significantly impaired due to non-cardiac problems.ConclusionTruncus arteriosus communis is a rare and complex cardiac anomaly that can be diagnosed prenatally with high precision. TAC is frequently associated with chromosomal and extra-cardiac anomalies, leading to a high intrauterine and postnatal loss rate due to terminations and perioperative mortality. Without severe extra-cardiac anomalies, postoperative health status is excellent, independent of the subtype of TAC, but the prevalence of repeated interventions due to recurrent stenosis is high.

DiGeorge syndrome presenting with seizure in neonatal period: a case report

DiGeorge syndrome is caused by a micro-deletion of chromosome 22q11.2 that disrupts development of the third and fourth pharyngeal pouches during early embryogenesis. Other structures forming at the same period are also frequently affected. So, the phenotypic spectrum shows a wide variability. In this case report, we describe a 1-month and 24-day old male child who presented with history of recurrent afebrile seizure and noisy breathing since early neonatal period. He had history of repeated chest infections. On examination, patient had stridor, facial dysmorphism, pectus excavatum and clinical features of pneumonia. Investigations revealed hypocalcaemia, hypoparathyroidism, consolidation on X-ray chest and cellular immunodeficiency. Echocardiography findings were normal. Fluorescent in situ hybridization (FISH) was performed which confirmed the diagnosis 22q11.2 deletion.&#x0D; Birdem Med J 2021; 11(2): 128-132

MLPA analysis of 32 foetuses with a congenital heart defect and 1 foetus with renal defects - pilot study. The significant frequency rate of presented pathological CNV.

The aim of this retrospective study was to determine the detection rate of the pathogenic copy number variants (CNVs) in a cohort of 33 foetuses - 32 with CHD (congenital heart defects) and 1 with kidney defect, after exclusion of common aneuploidies (trisomy 13, 18, 21, and monosomy X) by karyotyping, Multiplex ligation - dependent probe amplification (MLPA) and chromosomal microarray analysis (CMA). We also assess the effectivity of MLPA as a method of the first tier for quick and inexpensive detection of mutations, causing congenital malformations in foetuses. MLPA with probe mixes P070, P036 - Telomere 3 and 5, P245 - microdeletions, P250 - DiGeorge syndrome, and P311 - CHD (Congenital heart defects) was performed in 33 samples of amniotic fluid and chorionic villi. CMA was performed in 10 relevant cases. Pathogenic CNVs were found in 5 samples: microdeletions in region 22q11.2 (≈2 Mb) in two foetuses, one distal microdeletion of the 22q11.2 region containing genes LZTR1, CRKL, AIFM3 and SNAP29 (≈416 kb) in the foetus with bilateral renal agenesis, 8p23.1 (3.8 Mb) microdeletion syndrome and microdeletion in area 9q34.3 (1.7 Mb, Kleefstra syndrome). MLPA as an initial screening method revealed unambiguously pathogenic CNVs in 15.2 % of samples. Our study suggests that MLPA and CMA are a reliable and high-resolution technology and should be used as the first-tier test for prenatal diagnosis of congenital heart disease. Determination of the cause of the abnormality is crucial for genetic counselling and further management of the pregnancy.

ABO-Incompatible Heart Transplantation in Older Children Using Immune Modulation

Purpose ABO-incompatible (ABOi) heart transplantation (HTx) has become a standard approach for infants with low isohemagglutinin titers (ISO). ABOi HTx may also be safe for older pediatric patients with altered immune response, however, thresholds are yet to be defined. Methods Data on management, clinical course and ISO were analyzed from two patients undergoing ABOi HTx beyond infancy. Results A 4-yr old ABO-O girl with hypoplastic left heart syndrome developed refractive protein-losing enteropathy, effusions and edema shortly after Fontan palliation, in the context of AV valve regurgitation and ventricular dysfunction. She was listed for HTx and deemed high-risk due to elevated pulmonary vascular resistance, HLA sensitization (cPRA 81 %), and need for ventilatory support. Despite her age, ISO titers were only moderately high (anti-A 1:32; anti-B 1:16); she underwent ABOi HTx (donor ABO-B) with plasmapheresis, ATG and methylprednisolone induction which was expanded for rituximab and IVIG. She required temporary right ventricular support and dialysis after HTx. Immunosuppression was maintained with tacrolimus and mycophenolate mofetil (MMF), modified during the clinical course to now receiving sirolimus / MMF for the past 6 years. Her B-ISO titres never exceeded 1:2 post-transplant. She remains free of rejection and graft vasculopathy now 9.5 years post-HTx. Another 4-yr old ABO-O girl with microdeletion 22q11 syndrome, pulmonary atresia, ventricular septal defect and MAPCAs sustained coronary artery injury resulting in ventricular dysfunction, requiring ECMO followed by milrinone dependency. She was listed for HTx and was highly HLA sensitized (cPRA 92%). Desensitisation was initiated with rituximab and IVIG; her A-ISO (peak anti-A 1:128) dropped to 1:16 at which point her listing was opened to ABOi. She received an ABOi HTx (donor ABO-A) at age 5 11/12 years, not crossing donor-specific HLA antibodies, receiving plasma exchange, ATG induction and methylprednisolone. Maintenance therapy included tacrolimus and MMF. She remains free of rejection now 1.5 years post-HTx with anti-A titre never exceeding 1:4. Conclusion ABOi HTx can be performed safely in selected older pediatric patients if ISO are low even secondary to immune manipulation. This approach may offer a long-term HTx option for older children who are highly sensitized or in urgent need of transplantation.

Prenatal diagnosis and genetic analysis of two fetuses with paternally derived 17q12 microdeletions

To reported on two fetuses diagnosed with 17q12 microdeletion syndrome. The two fetuses were respectively found to have renal abnormalities and polyhydramnios upon second and third trimester ultrasonography. Umbilical cord blood of the first fetus and amniotic fluid of the second fetus were subjected to single nucleotide polymorphism array (SNP-array) analysis. After 17q12 microdeletion was found in the first fetus, SNP-array was carried out on peripheral blood samples of the parents to determine its origin. With the medical history of the parents taken into consideration, the father underwent high-throughput sequencing for 565 urinary system-related genes to exclude pathogenic or likely pathogenic variants associated with congenital malformations of the urinary and reproductive systems. In both fetuses, SNP-array has revealed a 1.42 Mb deletion at 17q12, or arr[hg19]17q12 (34 822 465-36 243 365) × 1. In both cases the microdeletion was inherited from the father, in whom no urinary disease-related pathogenic or likely pathogenic variants was identified. Paternally derived 17q12 microdeletions probably underlay the genetic etiology of the two fetuses with renal ultrasound abnormalities and polyhydramnios. SNP-array can enable the diagnosis and facilitate genetic counseling and prenatal diagnosis for the families.