Prenatal Phenotype of a Heterozygous de Novo Missense COL4A1 Variant in a Fetus With Pleural Effusion, Ascites, Increased Placental Thickness, Decreased Amniotic Fluid, and Cerebral Structural Malformations.

The term spinocerebellar ataxia encompasses a heterogeneous group of neurodegenerative disorders due to pathogenic variants in more than 100 genes, underlying 2 major groups of ataxia: autosomal dominant cerebellar ataxias (ADCA, also known as spinocerebellar ataxias [SCAs]) due to heterozygous variants or polyglutamine triplet expansions leading to adult-onset ataxia, and autosomal recessive spinocerebellar ataxias (ARCAs, also known as SCARs) due to biallelic variants, usually resulting in more severe and earlier-onset cerebellar ataxia. Certain ataxia genes, including SPTBN2 which encodes β-III spectrin, are responsible for both SCA and SCAR, depending on whether the pathogenic variant occurs in a monoallelic or biallelic state, respectively. Accordingly, 2 major phenotypes have been linked to SPTBN2: pathogenic heterozygous in-frame deletions and missense variants result in an adult-onset, slowly progressive ADCA (SCA5) through a dominant negative effect, whereas biallelic loss-of-function variants cause SCAR14, an allelic disorder characterized by infantile-onset cerebellar ataxia and cognitive impairment. Of note, 2 heterozygous missense variants (c.1438C>T, p.R480 W; c.1309C>G, p.R437G), both lying in the second spectrin repeat of SPTBN2, have been linked to infantile-onset cerebellar ataxia, similar to SCAR14. Here, we report a novel de novo heterozygous pathogenic missense variant (c.1310G>A) in SPTBN2 in a child with infantile-onset cerebellar ataxia and mild cognitive impairment. This variant affects the same R437 residue of the second spectrin repeat but results in a different amino acid change (p.R437Q). We review previously reported cases and discuss possible pathomechanisms responsible for the early-onset cerebellar phenotype due to disease-causing variants in the second spectrin repeat.

Background: von Willebrand Disease (VWD) is the most common hereditary coagulation disorder. Generally, coagulation disorders are more prevalent in communities with high rate of consanguinity. Due to segregation of multiple alleles, combinations of abnormal variants causing unique clinical presentations can occur. Aims: We aim to present our single centre experience of VWD in pediatrics. Methods: Retrospective data analysis of all pediatric patients diagnosed with (VWD) throughout a period of 10 years, dating from January 2012 till December 2021. In addition, molecular testing using next generation sequencing (NGS) of a family, with a spectrum of bleeding phenotypes was done. Results: Out of 455 cases with hereditary coagulation disorders, 219 (48%) were diagnosed with VWD throughout the study period (141 girls and 78 boys), with an age of presentation ranging from 18 months to 14 years. Significant bleeding episodes were encountered in 42/219 patients (19%). History of consanguinity was documented in 175 cases (80%). The most common presenting feature was mucocutaneous bleeding, followed by menorrhagia and then post-traumatic/post-surgical hemorrhage. Factor replacement therapy was used in 34 cases and desmopressin (DDAVP) in 22 cases. Hormonal therapy was offered to 18 girls presenting with menorrhagia. However, only 7 of them were compliant. The index case is a 4-year-old girl, presented with profuse post-adenotonsillectomy hemorrhage. Her past history was negative for any significant bleeding, but no previous surgical challenges. Parents are cousins, and family history was irrelevant. Routine preoperative investigations didn’t reveal any abnormalities apart from raised mean platelet volume (14 fL), and a platelet count of 180 × 10ˆ9/L. Bleeding didn’t respond optimally to FFP, but controlled with multiple platelet transfusions and recombinant activated factor VII. Molecular studies using NGS revealed two different heterozygous variants in the CD36 gene. The first heterozygous variant was NM_001001547.2:c338_339del (p.Ser113Phefs*20), a frameshift variant which results in loss of function of the protein product of CD36 gene. The second was deletion of exons 2 and 3 (NM_001001547.2:c.1_120del), which results in loss of a significant portion of the coding region of CD36 gene. To our knowledge, both novel variants have not been reported in the literature. Biallelic mutations in CD36 are associated with platelet glycoprotein IV deficiency (PG4D), characterized by macrothrombocytopenia with variable bleeding phenotype (PubMed: 7533783; OMIM: 173510). In addition, A heterozygous variant in the VWF gene, NM_000552.4:c.3692A>G (p.Asn1231Ser), was identified. This heterozygous variant was reported in a case with von Willebrand disease type 1 (PubMed: 28971901). The distinctive combination of these three variants explains the severe bleeding phenotype. NGS identified the same heterozygous frameshift variant of CD36 in the mother, while the father carries both the deletional variant of CD36 and the missense variant of VWF gene. Two sisters (ages: 8 & 15 years) harbor the heterozygous VWF gene variant. On further enquiries, the eldest was found to have mild to moderate menorrhagia, that didn’t require any medical advice. Family pedigree is shown in figure 1. Image:Summary/Conclusion: Genotype-phenotype correlation is mandatory in coagulation disorders, presenting with significant bleeding episodes.

<h3>Background and Aims</h3> Ductal plate malformation (DPM) includes polycystic liver disease (PCLD), multiple biliary hamartomas (MBH), congenital hepatic fibrosis (CHF) and Caroli disease. We sought to identify the genetic basis of a cohort of hitherto undefined DPM. <h3>Methods</h3> 34 unrelated adults with presumed congenital liver disease underwent extended genetic analysis via a clinical exome panel (PKD1, PKD2, PKHD1, SEC63, PRKCSH, GANAB, ALG8, DNAJB11, LRP5). Clinical details and phenotypic correlation were analysed. <h3>Results</h3> Of the 34 patients screened, genetic variants were identified in 20: Heterozygous variants in GANAB (n=4: 3 females, 1 male, mean age 56) were associated with a variety of mild PCLD phenotypes (with and without renal cysts, with Caroli’s and with MBH). Variants were pathogenic in 2 cases and were variants of unknown significance (VUS) in 2 cases (both deleterious). Heterozygous variants in PRKCSH (n=2: both female, mean age 62) were associated with PCLD without renal cysts including 1 VUS (deleterious) and 1 novel pathogenic variant in a patient considered for liver transplantation. Heterozygous variants in the SEC63 (n=4: 3 females, 1 male, mean age 60) were associated with largely asymptomatic PCLD mostly without renal cysts including 3 pathogenic (all novel) and 1 VUS (deleterious). PKD1 (n=3) and PKD2 (n=2) heterozygous gene variants (4 pathogenic including 2 novel) were associated with polycystic kidney and liver disease. All 5 were female (mean age 48) and with significant family history. Variants in PKHD1 (n=5: 4 male, 1 female, mean age 67 years) were mostly compound heterozygous and had a variety of phenotypes including CHF (n=2, both liver transplanted), CHF/MBH (n=1, portal hypertension), MBH/Caroli (n=1, kidney transplanted) and PCLD without renal cysts (n=1). In 14/34 patients, no genetic variants were identified. These included 3 CHF, 3 MBH and 8 PCLD patients. <h3>Conclusion</h3> Patients with DPM display a spectrum of disease phenotypes ranging in severity from asymptomatic, incidental diagnosis to end-stage liver disease. We identified the genetic cause in nearly 60% of a previously undefined cohort of DPM patients and discovered several novel variants. Of note, a significant proportion had meaningful variants in GANAB, PRKCSH and SEC63. PRKCSH and SEC63 variants were associated with isolated PCLD. GANAB and PKHD1 mutations were associated with mixed phenotypes, the latter found in mostly males and with a strong propensity for CHF. GANAB and SEC63 phenotypes were mild. Our findings support the use of bespoke gene panels in suspected DPM.

Biallelic variants in the WFS1 gene are associated with Wolfram syndrome. However, recent publications document that heterozygous variants can lead to a variety of phenotypes, such as Wolfram-like syndrome or isolated features of Wolfram syndrome. In this case report, we present a male patient with a history of congenital cataracts and subjective complaints of muscle weakness. Clinical assessment demonstrated normal muscle strength, and genomic, biochemical, electrophysiologic, and muscle biopsy studies did not identify a potential cause of the proband's perceived muscle weakness. Whole-exome sequencing identified a novel de novo variant in the WFS1 gene (c.1243G > T), representing one of only several patients in the published literature with isolated congenital cataracts and a heterozygous WFS1 variant. The variety of phenotypes associated with heterozygous variants in WFS1 suggests that this gene should be considered as a cause of both dominant and biallelic/recessive forms of disease. Future research should focus on elucidating the mechanism(s) of disease and variable expressivity in WFS1 in order to improve our ability to provide patients and families with anticipatory guidance about the disease, including appropriate screening and medical interventions.

Heterozygous Variants in the DNA-binding Domain of c-Myb May Affect Normal B/T Cell Development.

To study the role of selected cytokines and growth factors involved in the pathogenesis of fetal chylous pleural effusion. Seventeen fetuses with prenatal chylothorax at gestational age (GA) 17-29 weeks were enrolled as the study group during the period 2003-2005. Their pleural effusion (n = 17) and amniotic fluid (n = 17) were drawn when disease set in. Eleven fetuses received cordocentesis because of suspected fetal anemia. Forty-one normal fetuses without adverse perinatal outcome at GA 17-29 weeks received amniocentesis and were enrolled in the reference group. Levels of hepatocyte growth factor (HGF), stromal-derived factor-1(SDF-1), vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), macrophage migratory inhibition factor (MIF), and interleukin-6 (IL-6) were determined in the samples from both groups (amniotic fluid, pleural fluid, and cord blood from the study group and amniotic fluid from the reference group) by enzyme-linked immunoassay (EIA). No significant differences were observed in the amniotic fluids between the study group and the reference group regarding levels of IL-6, IL-8, MIF, SDF-1, HGF and VEGF. In the study group, levels of IL-8, VEGF and SDF-1 (all pro-angiogenic) showed no significant differences between the amniotic fluid, cord blood and pleural effusion. The level of HGF (proangiogenic) was significantly higher in the amniotic fluid than in the cord blood or the pleural effusion, but there were no significant differences between the levels in the pleural fluid and in the cord blood. Interestingly, the levels of MIF and IL-6 (both are proinflammatory) in the amniotic fluid and in the pleural effusion were much higher than the levels in the cord blood. Our study demonstrated that the levels of pro-inflammatory proteins (MIF and IL-6) that we tested were higher in the fetal pleural effusion than in the fetal circulation, a phenomenon not observed in the levels of proangiogenic proteins (HGF, SDF-1, VEGF, IL-8). This result implies that inflammation-related proteins may be more relevant than the angiogenesis-related proteins in the local environment of accumulating pleural effusion, a prominent feature of prenatal chylothorax.

A Multimodality Approach to Assessing Factor I Genetic Variants in Atypical Hemolytic Uremic Syndrome

Introduction: Inactivating mutations of the calcium-sensing receptor (CASR) gene result in neonatal severe hyperparathyroidism (NSHPT). Total parathyroidectomy is an effective way to control life-threatening hypercalcemia in NSHPT but leads to permanent hypoparathyroidism. An alternative surgical option is subtotal parathyroidectomy. However, few cases were reported in the literature. Here, we report two unrelated NSHPT patients, one with a novel homozygous mutation (c.1817T>C; p.Leu606Pro) in CASRand the other with heterozygous for the same mutation who also carried two rare intronic variants in CASR. The outcomes of subtotal parathyroidectomy in these patients are also described. Case Presentation: Two infants presented with an alteration of consciousness, respiratory distress, and bradycardia. Severe hypercalcemia, hypophosphatemia, and markedly elevated parathyroid hormone levels were identified, suggesting NSHPT. Cinacalcet was unable to control calcium (Ca) levels of both patients. A novel heterozygous and homozygous missense mutation c.1817T>C; p.Leu606Pro was identified in patients 1 and 2, respectively. Based on the model prediction, proline substitution at Leu606 is likely to disrupt conversion between the active and inactive conformations at the extracellular to transmembrane domain interface of CASR. In addition, two extremely rare intronic variants in CASR (chr3:g.122180314A>G and chr3:g.122251601G>A, based on GRCh38) were identified in patient 1 and his mother. These variants might have contributed to the clinical manifestations of patient 1 who was heterozygous for the c.1817T>C; p.Leu606Pro variant. Subtotal parathyroidectomy was performed by removing three and a half parathyroid glands. So far, patient 1 has been in normocalcemia for 5 years. Patient 2 was in normocalcemia for 16 months after surgery and subsequently developed mild hypoparathyroidism which required only low-dose calcitriol treatment. Conclusion: We report a novel heterozygous and homozygous missense variant (c.1817T>C; p.Leu606Pro) in CASR in two NSHPT patients. The mutation likely disrupts conformational changes of CASR and results in cinacalcet unresponsiveness. Intronic variants in CASR identified in the patient with heterozygous variant might have contributed to the clinical manifestations of the patient. Although total parathyroidectomy is widely accepted as a standard treatment for NSHPT, we demonstrate that subtotal parathyroidectomy is also an effective procedure to normalize Ca levels and allow these patients to be in normocalcemia or mild hypoparathyroidism, which is simply controlled by low-dose calcitriol treatment. Subtotal parathyroidectomy appeared to be an effective treatment for NSHPT regardless of the molecular etiologies.

Around 180 genes have been associated with congenital anomalies of the kidney and urinary tract (CAKUT) in mice, and represent promising novel candidate genes for human CAKUT. In whole-exome sequencing data of two siblings with genetically unresolved multicystic dysplastic kidneys (MCDK), prioritizing variants in murine CAKUT-associated genes yielded a rare variant in the teashirt zinc finger homeobox 3 (TSHZ3) gene. Therefore, the role of TSHZ3 in human CAKUT was assessed. Twelve CAKUT patients from 9/301 (3%) families carried five different rare heterozygous TSHZ3 missense variants predicted to be deleterious. CAKUT patients with versus without TSHZ3 variants were more likely to present with hydronephrosis, hydroureter, ureteropelvic junction obstruction, MCDK, and with genital anomalies, developmental delay, overlapping with the previously described phenotypes in Tshz3-mutant mice and patients with heterozygous 19q12-q13.11 deletions encompassing the TSHZ3 locus. Comparable with Tshz3-mutant mice, the smooth muscle layer was disorganized in the renal pelvis and thinner in the proximal ureter of the nephrectomy specimen of a TSHZ3 variant carrier compared to controls. TSHZ3 was expressed in the human fetal kidney, and strongly at embryonic day 11.5-14.5 in mesenchymal compartments of the murine ureter, kidney, and bladder. TSHZ3 variants in a 5′ region were more frequent in CAKUT patients than in gnomAD samples (p < 0.001). Mutant TSHZ3 harboring N-terminal variants showed significantly altered SOX9 and/or myocardin binding, possibly adversely affecting smooth muscle differentiation. Our results provide evidence that heterozygous TSHZ3 variants are associated with human CAKUT, particularly MCDK, hydronephrosis, and hydroureter, and, inconsistently, with specific extrarenal features, including genital anomalies.

Heterozygous Variants in the Mechanosensitive Ion Channel TMEM63A Result in Transient Hypomyelination during Infancy

Introduction CARD8 encodes the caspase recruitment domain-containing protein 8, a negative regulator of the NLRP3 inflammasome and a modulator of innate immune signaling. Although not yet formally classified among inborn errors of immunity (IEIs), emerging evidence suggests a potential role of CARD8 variants in autoinflammatory syndromes and immune dysregulation. Case Presentations We describe three unrelated patients from different families with variable phenotypes involving autoinflammation and immune dysregulation. Patient 1: A 15-year-old female with an IPEX (immune dysregulation, polyendocrinopathy, enteropathy, X-linked)-like phenotype, including alopecia universalis, growth retardation, pubertal delay, and elevated serum IL-18 levels. A heterozygous frameshift variant in CARD8 (c.40delG, p.Glu14fs) was identified. Patient 2: A 3-year-old male presenting with neonatal lupus-like rash, severe atopic dermatitis, refractory autoimmune cytopenias, persistent hepatitis, and total villous atrophy on intestinal biopsy (Marsh 3b). A heterozygous frameshift variant (c.68dupG, p.Ser24fs) was detected. Patient 3: A 42-year-old female with adult-onset CVID (common variable immunodeficiency)-like phenotype, including recurrent pneumonia, chronic diarrhea, and persistent hypogammaglobulinemia requiring immunoglobulin replacement. A heterozygous missense variant (c.1093A&amp;gt;C, p.Met365Leu) was identified. Discussion These cases illustrate the broad clinical spectrum associated with CARD8 variants, ranging from severe early-onset autoinflammatory disease to adult-onset humoral immunodeficiency. The presence of elevated IL-18 and multi-organ involvement supports dysregulated inflammasome activation as a key pathogenic mechanism. Importantly, heterozygous variants may result in incomplete penetrance and variable expressivity, complicating diagnosis and counseling. Conclusion CARD8 mutations should be considered in patients presenting with unexplained autoinflammation, immune dysregulation, or CVID-like phenotypes. Recognition of this spectrum may facilitate earlier diagnosis, appropriate therapeutic interventions targeting IL-1/IL-18 pathways, and genetic counseling for affected families.

Warsaw Breakage Syndrome (WABS) is a rare autosomal recessive cohesinopathy characterized by growth retardation and congenital anomalies. This report aims to highlight the prenatal diagnosis of WABS through ultrasound findings and genetic testing. We report a case of prenatal diagnosis of WABS in a 24-week gestation fetus exhibiting microcephaly, delayed sulcation, short corpus callosum, cerebellar vermis hypoplasia and intrahepatic portal-systemic shunts. The couple had a history of a prior pregnancy termination due to severe intrauterine growth restriction and cerebral malformations. Whole exome sequencing revealed compound heterozygous pathogenic variants [NM_030653.4:c.1403dupT, p.(Ser469Valfs*32) and c.1672C>T, p.(Arg558*)] in the DDX11 gene, consistent with WABS. The same pathogenic variants were identified in the prior terminated fetus upon subsequent analysis. Postmortem examination of the proband confirmed the prenatal ultrasound findings. This case expands the understanding of the prenatal phenotypic spectrum of WABS by identifying specific cerebral and extracerebral anomalies associated with pathogenic variants in the DDX11 gene. Incorporating advanced genetic diagnostics like whole exome sequencing into prenatal care provides valuable information for genetic counseling and management of rare genetic disorders.

PurposeWhole-exome sequencing (WES) of multiplex families is a promising strategy for identifying causative variations for common diseases. To identify rare recessive risk variations for schizophrenia, we performed a WES study in a consanguineous family with affected siblings. We then performed follow-up sequencing of SPATA7 in schizophrenia-affected families. In addition, we performed a case-control study to investigate association between SPATA7 variations and schizophrenia.Patients and methodsWES was performed on two affected siblings and their unaffected parents, who were second cousins, of a multiplex schizophrenia family. Subsequently, we sequenced the coding region of SPATA7, a potential risk gene identified by the WES analysis, in 142 affected offspring from 137 families for whom parental DNA samples were available. We further tested rare recessive SPATA7 variations, identified by WES and sequencing, for associations with schizophrenia in 2,756 patients and 2,646 controls.ResultsOur WES analysis identified rare compound heterozygous missense SPATA7 variations, p.Asp134Gly and p.Ile332Thr, in both affected siblings. Sequencing SPATA7 coding regions from 137 families identified no rare recessive variations in affected offspring. In the case-control study, we did not detect the rare compound heterozygous SPATA7 missense variations in patients or controls.ConclusionOur data does not support the role of the rare compound heterozygous SPATA7 missense variations p.Asp134Gly and p.Ile332Thr in conferring a substantial risk of schizophrenia.

Sir, We report a case of prenatally diagnosed congenital diaphragmatic hernia (CDH) presenting with massive ascites and pleural effusion caused by intrauterine perforation of an incarcerated stomach through a small diaphragmatic defect. A 25-year-old woman, gravida 0, para 0, underwent a prenatal US scan at 31 weeks of gestational age (GA). Left-side CDH was detected in the fetus. Pleural effusion and polyhydramnios were observed at 32 weeks’ GA. Aspiration of the fetal pleural effusion revealed that it contained numerous squamous cells and neutrophils, indicating the presence of gastrointestinal perforation. Fetal MRI at 34 weeks’ GA demonstrated herniation of the stomach and intestine through a small defect in the diaphragm, as well as massive ascites and pleural effusion (Fig. 1). The liver was not herniated. The ascites and pleural effusion had the same intensity as the gastric contents and the amniotic fluid, but not as the meconium. These findings strongly suggested gastric perforation due to incarceration, resulting in massive pleural effusion and ascites, rather than intestinal perforation resulting in meconium peritonitis or pleuritis. At 35 weeks’ GA, the fetus showed hydrops with marked polyhydramnios. The female baby was subsequently delivered by Caesarian section at 36 weeks’ GA with a birth weight of 3,246 g. The baby was intubated immediately and highfrequency oscillatory ventilation and nitric oxide therapy were initiated. Radiographs showed marked generalised oedema, mediastinal shift to the right and gastric air in the left thoracic cavity. No intestinal gas or calcification was seen. Respiratory parameters improved soon after left thoracic drainage of 450 ml non-bilious pleural effusion, which also contained hair. The baby underwent CDH repair at 1 day of age. The poorly perfused stomach and small intestines were herniated through a slit-like diaphragmatic defect of 1.5 cm in length. After reduction of the hernia, a pinhole perforation was found in the stomach just proximal to the pylorus and repaired by direct closure. The stomach and intestines were viable. The small diaphragmatic defect was closed primarily. The baby recovered promptly from respiratory failure as well as from pleuritis and peritonitis. There have been only a few case reports of neonatal CDH presenting with gastric [1, 2] or intestinal [3–5] perforation. Most cases were discovered after birth as pneumothorax, meconium thorax or meconium peritonitis [2–5]. In our case, fetal MRI and aspiration of the pleural effusion were greatly helpful in prenatal diagnosis. There was one similar case of CDH presenting with gastrointestinal perforation with massive ascites and pleural effusion, which was observed on prenatal US [1]. Our case highlights the importance of fetal MRI in the diagnosis of intrauterine gastric perforation in CDH; MRI was greatly informative, demonstrating incarceration of the stomach and intestine through a small defect clearly as well H. Komuro : C. Gotoh Department of Pediatric Surgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan

Heterozygous variants in Transient receptor potential melastatin type 7 (TRPM7), encoding an essential and ubiquitously expressed cation channel, may cause hypomagnesemia, but current evidence is insufficient to draw definite conclusions and it is unclear whether any other phenotypes can occur. Individuals with unexplained hypomagnesemia underwent whole-exome sequencing which identified TRPM7 variants. Pathogenicity of the identified variants was assessed by combining phenotypic, functional and in silico analyses. We report three new heterozygous missense variants in TRPM7 (p.Met1000Thr, p.Gly1046Arg, p.Leu1081Arg) in individuals with hypomagnesemia. Strikingly, autism spectrum disorder and developmental delay, mainly affecting speech and motor skills, was observed in all three individuals, while two out of three also presented with seizures. The three variants are predicted to be severely damaging by in silico prediction tools and structural modeling. Furthermore, these variants result in a clear loss-of-function of TRPM7-mediated magnesium uptake in vitro, while not affecting TRPM7 expression or insertion into the plasma membrane. This study provides additional evidence for the association between heterozygous TRPM7 variants and hypomagnesemia and adds developmental delay to the phenotypic spectrum of TRPM7-related disorders. Considering that the TRPM7 gene is relatively tolerant to loss-of-function variants, future research should aim to unravel by what mechanisms specific heterozygous TRPM7 variants can cause disease.