Variants in FOXC1 and FOXC2 identified in patients with conotruncal heart defects.

Conotruncal heart defects (CTD), subtypes of congenital heart disease, result from abnormal cardiac outflow tract development (OFT). FOXC1 and FOXC2 are closely related members of the forkhead transcription factor family and play essential roles in the development of OFT. We confirmed their expression pattern in mouse and human embryos, identifying four variants in FOXC1 and three in FOXC2 by screening these two genes in 605 patients with sporadic CTD. Western blot demonstrated expression levels, while Dual-luciferase reporter assay revealed affected transcriptional abilities for TBX1 enhancer in two FOXC1 variants and three FOXC2 variants. This might result from the altered DNA-binding abilities of mutant proteins. These results indicate that functionally impaired FOXC1 and FOXC2 variants may contribute to the occurrence of CTD.

Maternal exposure to ambient ozone and fetal conotruncal heart defects in China: A multicenter cohort study.

BACKGROUND: The relationships between maternal genetic and environmental exposure and conotruncal heart defects (CTDs) have been extensively investigated. Nevertheless, there is limited knowledge regarding the impact of ozone (O3) on the risk of CTDs. OBJECTIVE: To explore the correlation between maternal exposure to O3 and CTDs in China. METHODS: Pregnant women who underwent fetal echocardiography at Beijing Anzhen Hospital between January 2013 and December 2021 were enrolled. Their sociodemographic characteristics and lifestyle information, along with fetal data, were systematically collected. Fetal echocardiography was used to detect CTDs. Maternal exposure to ambient O3 during the embryonic period, the first trimester, the three months preceding the last menstrual period, and the perinatal period was estimated using residential addresses or hospital addresses associated with prenatal visits. The concentration of O3 was divided by quartiles, with the first quartile serving as a reference. Adjusted logistic regression models were employed to examine the associations between every 10 µg/m3 increase or quartile increase in ambient O3 exposure and CTDs. RESULTS: Among 24,278 subjects, 1069 exhibited fetuses with CTDs. Maternal exposure to ambient O3 during three pregnancy periods was associated with increased CTD risk. The adjusted odds ratio (OR) and 95% confidence interval (CI) were 1.271 (1.189-1.360) per 10 µg/m3 increase in O3 during the perinatal period. For each quartile of O3, the risk increased with increasing exposure concentration, particularly during the perinatal period (OR = 2.206 for quartile 2, 2.367 for quartile 3, and 3.378 for quartile 4, all P<0.05). CONCLUSIONS: Elevated maternal exposure to O3 during pregnancy, particularly in the perinatal period, is linked to an increased risk of fetal CTDs. Further longitudinal analyses are needed to validate these results.

Analysis of pathogenic variants in 605 Chinese children with non-syndromic cardiac conotruncal defects based on targeted sequencing.

OBJECTIVE: Deleterious genetic variants comprise one cause of cardiac conotruncal defects (CTDs). Genes associated with CTDs are gradually being identified. In the present study, we aimed to explore the profile of genetic variants of CTD-associated genes in Chinese patients with non-syndromic CTDs. METHODS: Thirty-nine CTD-related genes were selected after reviewing published articles in NCBI, HGMD, OMIM, and HPO. In total, 605 patients with non-syndromic CTDs and 300 healthy controls, all of Han ethnicity, were recruited. High-throughput targeted sequencing was used to detect genetic variants in the protein-coding regions of genes. We performed rigorous variant-level filtrations to identify potentially damaging variants (Dvars) using prediction programs including CADD, SIFT, PolyPhen-2, and MutationTaster. RESULT: Dvars were detected in 66.7% (26/39) of the targeted CTD-associated genes. In total, 11.07% (67/605) of patients with non-syndromic CTDs were found to carry one or more Dvars in targeted CTD-associated genes. Dvars in FOXH1, TBX2, NFATC1, FOXC2, and FOXC1 were common in the CTD cohort (1.5% [9/605], 1.2% [7/605], 1.2% [7/605], 1% [6/605], and 0.5% [3/605], respectively). CONCLUSION: Targeted exon sequencing is a cost-effective approach for the genetic diagnosis of CTDs. Our findings contribute to an understanding of the genetic architecture of non-syndromic CTDs.

Complete Sequence of the 22q11.2 Allele in 1,053 Subjects with 22q11.2 Deletion Syndrome Reveals Modifiers of Conotruncal Heart Defects.

The 22q11.2 deletion syndrome (22q11.2DS) results from non-allelic homologous recombination between low-copy repeats termed LCR22. About 60%-70% of individuals with the typical 3 megabase (Mb) deletion from LCR22A-D have congenital heart disease, mostly of the conotruncal type (CTD), whereas others have normal cardiac anatomy. In this study, we tested whether variants in the hemizygous LCR22A-D region are associated with risk for CTDs on the basis of the sequence of the 22q11.2 region from 1,053 22q11.2DS individuals. We found a significant association (FDR p < 0.05) of the CTD subset with 62 common variants in a single linkage disequilibrium (LD) block in a 350 kb interval harboring CRKL. A total of 45 of the 62 variants were associated with increased risk for CTDs (odds ratio [OR) ranges: 1.64-4.75). Associations of four variants were replicated in a meta-analysis of three genome-wide association studies of CTDs in affected individuals without 22q11.2DS. One of the replicated variants, rs178252, is located in an open chromatin region and resides in the double-elite enhancer, GH22J020947, that is predicted to regulate CRKL (CRK-like proto-oncogene, cytoplasmic adaptor) expression. Approximately 23% of patients with nested LCR22C-D deletions have CTDs, and inactivation of Crkl in mice causes CTDs, thus implicating this gene as a modifier. Rs178252 and rs6004160 are expression quantitative trait loci (eQTLs) of CRKL. Furthermore, set-based tests identified an enhancer that is predicted to target CRKL and is significantly associated with CTD risk (GH22J020946, sequence kernal association test (SKAT) p = 7.21 × 10-5) in the 22q11.2DS cohort. These findings suggest that variance in CTD penetrance in the 22q11.2DS population can be explained in part by variants affecting CRKL expression.

Expanded cardiovascular phenotype of Myhre syndrome includes tetralogy of Fallot suggesting a role for SMAD4 in human neural crest defects.

Tetralogy of Fallot (ToF) can be associated with a wide range of extracardiac anomalies, with an underlying etiology identified in approximately 10% of cases. Individuals affected with Myhre syndrome due to recurrent SMAD4 mutations frequently have cardiovascular anomalies, including congenital heart defects. In addition to two patients in the literature with ToF, we describe five additional individuals with Myhre syndrome and classic ToF, ToF with pulmonary atresia and multiple aorto-pulmonary collaterals, and ToF with absent pulmonary valve. Aorta hypoplasia was documented in one patient and suspected in another two. In half of these individuals, postoperative cardiac dysfunction was thought to be more severe than classic postoperative ToF repair. There may be an increase in right ventricular pressure, and right ventricular dysfunction due to free pulmonic regurgitation. Noncardiac developmental abnormalities in our series and the literature, including corectopia, heterochromia iridis, and congenital miosis suggest an underlying defect of neural crest cell migration in Myhre syndrome. We advise clinicians that Myhre syndrome should be considered in the genetic evaluation of a child with ToF, short stature, unusual facial features, and developmental delay, as these children may be at risk for increased postoperative morbidity. Additional research is needed to investigate the hypothesis that postoperative hemodynamics in these patients may be consistent with restrictive myocardial physiology.

Array comparative genomic hybridisation results of non-syndromic children with the conotruncal heart anomaly.

The study aimed to show the chromosomal copy number variations responsible for the aetiology in patients with isolated conotruncal heart anomaly by array comparative genomic hybridisation and identify candidate genes causing conotruncal heart disease. A total of 37 patients, 17 male, and 20 female, with isolated conotruncal heart anomalies, were included in the study. No findings indicated any syndrome in terms of dysmorphology in the patients. RESULTS: Copy number variations were detected in the array comparative genomic hybridisation analysis of five (13.5%) of 37 patients included in the study. Three candidate genes (PRDM16, HIST1H1E, GJA5) found in these deletion and duplication regions may be associated with the conotruncal cardiac anomaly. CONCLUSION: CHDs can be encountered as the first and sometimes the single finding of many genetic disorders in children. It is thought that genetic tests, especially array comparative genomic hybridisation, may be beneficial for children with CHD since the diagnosis of genetic diseases in these patients as early as possible will help to prevent or reduce complications that may develop in the future. Also, it would be possible to detect candidate genes responsible for conotruncal cardiac anomalies with array comparative genomic hybridisation.

Novel mutations of the SRF gene in Chinese sporadic conotruncal heart defect patients.

BACKGROUND: Conotruncal heart defects (CTDs) are a group of congenital heart malformations that cause anomalies of cardiac outflow tracts. In the past few decades, many genes related to CTDs have been reported. Serum response factor (SRF) is a ubiquitous nuclear protein that acts as transcription factor, and SRF was found to be a critical factor in heart development and to be strongly expressed in the myocardium of the developing mouse and chicken hearts. The targeted inactivation of SRF during heart development leads to embryonic lethality and myocardial defects in mice. METHODS: To illustrate the relationship between SRF and human heart defects, we screened SRF mutations in 527 CTD patients, a cross sectional study. DNA was extracted from peripheral leukocyte cells for target sequencing. The mutations of SRF were detected and validated by Sanger sequencing. The affection of the mutations on wild-type protein was analyzed by in silico softwares. Western blot and real time PCR were used to analyze the changes of the expression of the mutant mRNA and protein. In addition, we carried out dual luciferase reporter assay to explore the transcriptional activity of the mutant SRF. RESULTS: Among the target sequencing results of 527 patients, two novel mutations (Mut1: c.821A > G p.G274D, the adenine(A) was mutated to guanine(G) at position 821 of the SRF gene coding sequences (CDS), lead to the Glycine(G) mutated to Asparticacid(D) at position 274 of the SRF protein amino acid sequences; Mut2: c.880G > T p.G294C, the guanine(G) was mutated to thymine (T) at position 880 of the SRF CDS, lead to the Glycine(G) mutated to Cysteine (C) at position 294 of the SRF protein amino acid sequences.) of SRF (NM_003131.4) were identified. Western blotting and real-time PCR showed that there were no obvious differences between the protein expression and mRNA transcription of mutants and wild-type SRF. A dual luciferase reporter assay showed that both SRF mutants (G274D and G294C) impaired SRF transcriptional activity at the SRF promoter and atrial natriuretic factor (ANF) promoter (p < 0.05), additionally, the mutants displayed reduced synergism with GATA4. CONCLUSION: These results suggest that SRF-p.G274D and SRF-p.G294C may have potential pathogenic effects.

Identification of FOXH1 mutations in patients with sporadic conotruncal heart defect.

Conotruncal heart defects (CTD) are an important subtype of congenital heart disease that occur due to abnormality in the development of the cardiac outflow tract (OFT). FOXH1 is a transcription factor that participates in the morphogenesis of the right ventricle and OFT. In this study, we confirmed the expression of FOXH1 in mouse and human embryos during OFT development. We also scanned the coding exons and splicing regions of the FOXH1 gene in 605 patients with sporadic CTD and 300 unaffected controls, from which we identified seven heterozygous FOXH1 gene mutations. According to bioinformatics analysis results, they were predicted potentially deleterious at conserved amino acid sites. Western blot was used to show that all the variants decreased the expression of FOXH1 protein, while dual-luciferase reporter assay showed that six of them, with an exception of p.P35R, had enhanced abilities to modulate the expression of MEF2C, which interacts with NKX2.5 and is involved in cardiac growth. The electrophoretic mobility shift assays result showed that two mutations altered DNA-binding abilities of mutant FOXH1 proteins. Phenotype heterogeneity was found in patients with the same mutation. These results indicate that FOXH1 mutations lead to disease-causing functional changes that contribute to the occurrence of CTD.

T-cell Receptor Excision Circles in Newborns with Heart Defects.

In the fetus, the cardiac neural crest gives rise to both the thymus and the conotruncus of the heart. In newborn screening for severe T-cell lymphopenia neonates with congenital heart defects may be detected. In this study, we investigated the occurrence of T-cell lymphopenia in neonates with or without 22q11.2 deletion syndrome (del) suffering from heart defects. This retrospective cohort study included 125 patients with heart defects. T-cell receptor excision circles (TRECs), a measure for T-cell lymphopenia, were quantified by RT-PCR using stored newborn screening blood spots. Three patient groups were compared: non-conotruncal defects (n = 57), conotruncal defects (n = 42), and 22q11.2 del with conotruncal defects (n = 26). Significantly lower TREC values were detected in patients with 22q11.2 del and conotruncal heart defects compared to those with non-syndromic conotruncal (p < 0.001) and non-conotruncal (p < 0.001) defects. In contrast, no significant difference was found between patients with non-syndromic conotruncal and non-conotruncal heart defects (p = 0.152). Low TREC levels were obtained in neonates treated with heart surgery/intervention within 2 weeks after birth and in those with a fatal outcome (p = 0.02) independent of patient group. A correlation was found between low TREC numbers and oxygen saturation, SpO2 below 95% (p = 0.017). The SpO2 was significantly lower in the non-syndromic conotruncal group compared to non-conotruncal (p < 0.001) and 22q11.2 del group (p = 0.015). No correlation was found between low neonatal TRECs and infections needing hospitalization later in life (p = 0.135). Patients with 22q11.2 del and conotruncal defects have significantly lower TREC levels compared to patients with heart defects without this syndrome.

Identification of TBX2 and TBX3 variants in patients with conotruncal heart defects by target sequencing.

BACKGROUND: Conotruncal heart defects (CTDs) are heterogeneous congenital heart malformations that result from outflow tract dysplasia; however, the genetic determinants underlying CTDs remain unclear. Increasing evidence demonstrates that dysfunctional TBX2 and TBX3 result in outflow tract malformations, implying that both of them are involved in CTD pathogenesis. We screened for TBX2 and TBX3 variants in a large cohort of CTD patients (n = 588) and population-matched healthy controls (n = 300) by target sequencing and genetically analyzed the expression and function of these variants. RESULTS: The probably damaging variants p.R608W, p.T249I, and p.R616Q of TBX2 and p.A192T, p.M65L, and p.A562V of TBX3 were identified in CTD patients, but none in controls. All altered amino acids were highly conserved evolutionarily. Moreover, our data suggested that mRNA and protein expressions of TBX2 and TBX3 variants were altered compared with those of the wild-type. We screened PEA3 and MEF2C as novel downstream genes of TBX2 and TBX3, respectively. Functional analysis revealed that TBX2R608W and TBX2R616Q variant proteins further activated HAS2 promoter but failed to activate PEA3 promoter and that TBX3A192T and TBX3A562V variant proteins showed a reduced transcriptional activity over MEF2C promoter. CONCLUSIONS: Our results indicate that the R608W and R616Q variants of TBX2 as well as the A192T and A562V variants of TBX3 contribute to CTD etiology; this was the first association of variants of TBX2 and TBX3 to CTDs based on a large population.

Identification of ZFPM2 mutations in sporadic conotruncal heart defect patients.

Conotruncal heart defects (CTDs) are a group of cardiac malformations that involve outflow tract anomalies and the arterial pole of the heart. Recent reports have identified mutations in a number of genes associated with CTDs in human and animal models. ZFPM2 plays a role in cardiac development by acting as a transcriptional cofactor that interacts with GATA4. Because ZFPM2 was found to be important for cardiac development in a knockout mouse model, we screened for ZFPM2 mutations in 528 CTD patients. We identified six rare and nonsynonymous ZFPM2 variants, and this was the first time that five of these variants (R698Q, R736L, E1005K, T32A, and I488V) were reported in East Asians. Western blots showed that there was no significant difference in the protein expression of wild-type ZFPM2, ZFPM2R698Q, or ZFPM2R736L. A dual luciferase reporter assay demonstrated that both ZFPM2 mutants R698Q and R736L reduced GATA4-mediated transcription. However, when ZFPM2R698Q was co-transfected with GATA4, BNP promoter activity increased significantly, whereas co-transfection with ZFPM2R736L and GATA4 did not significantly increase BNP promoter activity. This suggests that the R698Q mutation may affect the ability of ZFPM2 to bind GATA4.

A parent-of-origin analysis of paternal genetic variants and increased risk of conotruncal heart defects.

The association between conotruncal heart defects (CTHDs) and maternal genetic and environmental exposures is well studied. However, little is known about paternal genetic or environmental exposures and risk of CTHDs. We assessed the effect of paternal genetic variants in the folate, homocysteine, and transsulfuration pathways on risk of CTHDs in offspring. We utilized National Birth Defects Prevention Study data to conduct a family-based case only study using 616 live-born infants with CTHDs, born October 1997-August 2008. Maternal, paternal and infant DNA was genotyped using an Illumina® Golden Gate custom single nucleotide polymorphism (SNP) panel. Relative risks (RR) and 95% confidence intervals (CI) from log-linear models determined parent of origin effects for 921 SNPs in 60 candidate genes involved in the folate, homocysteine, and transsulfuration pathways on risk of CTHDs. The risk of CTHD among children who inherited a paternally derived copy of the A allele on GLRX (rs17085159) or the T allele of GLRX (rs12109442) was 0.23 (95%CI: 0.12, 0.42; p = 1.09 × 10-6 ) and 0.27 (95%CI: 0.14, 0.50; p = 2.06 × 10-5 ) times the risk among children who inherited a maternal copy of the same allele. The paternally inherited copy of the GSR (rs7818511) A allele had a 0.31 (95%CI: 0.18, 0.53; p = 9.94 × 10-6 ] risk of CTHD compared to children with the maternal copy of the same allele. The risk of CTHD is less influenced by variants in paternal genes involved in the folate, homocysteine, or transsulfuration pathways than variants in maternal genes in those pathways.

In Silico Analyses Reveal the Relationship Between SIX1/EYA1 Mutations and Conotruncal Heart Defects.

Conotruncal heart defects (CTDs) represent a group of severe and complicated congenital cardiovascular malformations and require opportune clinical interventions once diagnosed. Occurrence of CTD is related to the functional abnormality of the second heart field (SHF), and variants of genes which regulate the development of the second heart field have been recognized as the main genetic factors leading to CTDs. Previous studies indicated that transcriptional complex SIX1/EYA1 may contribute to SHF development, and SIX1/EYA1 knockout mice exhibited a series of conotruncal malformations. Here, we recruited and sequenced 600 Chinese conotruncal heart defect patients and 300 controls. We screened out one novel SIX1 mutation (SIX1-K134R) and four EYA1 rare mutations (EYA1-A227T, EYA1-R296H, EYA1-Q397R, EYA1-G426S), all variants were present only in the case cohort, and the mutated sites were highly conserved. We then analyzed mutations by software including Sift, PolyPhen-2, PROVEAN, Mutation Taster, HOPE, and SWISS-PdbViewer. The results showed that the mutations had varying degrees of pathogenic risk, protein properties, spatial conformations, and domain functions which might be altered or influenced. Through biological and in silico analyses, our study suggests an association between SIX1/EYA1 mutations and cardiovascular malformations, SIX1/EYA1 mutations might be partially responsible for CTDs.

Genetic variance of transforming growth factor ß2 gene in conotruncal heart defects.

OBJECTIVE: The aim of this study was to evaluate the association between two haplotype-tag single nucleotide polymorphisms (SNPs) (rs6658835 and rs10495098) of TGF-ß2 and conotruncal heart defects (CTDs). METHODS: Two polymorphisms of TGF-ß2 gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) from 259 CTDs patients and 310 control subjects. RESULTS: The association between SNP rs6658835 in TGF-ß2 and CTDs has been found. The frequency of G allele in CTDs patients was significantly higher than that in control subjects (52.7% versus 40.3%, p < 0.001, OR =1.649). CONCLUSION: TGF-ß2 gene polymorphisms may serve as a novel genetic marker for the risk of CTDs.

MESP1 Mutations in Patients with Congenital Heart Defects.

Identifying the genetic etiology of congenital heart disease (CHD) has been challenging despite being one of the most common congenital malformations in humans. We previously identified a microdeletion in a patient with a ventricular septal defect containing over 40 genes including MESP1 (mesoderm posterior basic helix-loop-helix transcription factor 1). Because of the importance of MESP1 as an early regulator of cardiac development in both in vivo and in vitro studies, we tested for MESP1 mutations in 647 patients with congenital conotruncal and related heart defects. We identified six rare, nonsynonymous variants not seen in ethnically matched controls and one likely race-specific nonsynonymous variant. Functional analyses revealed that three of these variants altered activation of transcription by MESP1. Two of the deleterious variants are located within the conserved HLH domain and thus impair the protein-protein interaction of MESP1 and E47. The third deleterious variant was a loss-of-function frameshift mutation. Our results suggest that pathologic variants in MESP1 may contribute to the development of CHD and that additional protein partners and downstream targets could likewise contribute to the wide range of causes for CHD.

Identification of novel candidate gene loci and increased sex chromosome aneuploidy among infants with conotruncal heart defects.

Congenital heart defects (CHDs) are common malformations, affecting four to eight per 1,000 total births. Conotruncal defects are an important pathogenetic subset of CHDs, comprising nearly 20% of the total. Although both environmental and genetic factors are known to contribute to the occurrence of conotruncal defects, the causes remain unknown for most. To identify novel candidate genes/loci, we used array comparative genomic hybridization to detect chromosomal microdeletions/duplications. From a population base of 974,579 total births born during 1999-2004, we screened 389 California infants born with tetralogy of Fallot or d-transposition of the great arteries. We found that 1.7% (5/288) of males with a conotruncal defect had sex chromosome aneuploidy, a sevenfold increased frequency (relative risk = 7.0; 95% confidence interval 2.9-16.9). We identified eight chromosomal microdeletions/duplications for conotruncal defects. From these duplications and deletions, we found five high priority candidate genes (GATA4, CRKL, BMPR1A, SNAI2, and ZFHX4). This is the initial report that sex chromosome aneuploidy is associated with conotruncal defects among boys. These chromosomal microduplications/deletions provide evidence that GATA4, SNAI2, and CRKL are highly dosage sensitive genes involved in outflow tract development. Genome wide screening for copy number variation can be productive for identifying novel genes/loci contributing to non-syndromic common malformations.

Conotruncal heart defects and common variants in maternal and fetal genes in folate, homocysteine, and transsulfuration pathways.

BACKGROUND: We investigated the association between conotruncal heart defects (CTDs) and maternal and fetal single nucleotide polymorphisms (SNPs) in 60 genes in the folate, homocysteine, and transsulfuration pathways. We also investigated whether periconceptional maternal folic acid supplementation modified associations between CTDs and SNPs METHODS: Participants were enrolled in the National Birth Defects Prevention Study between 1997 and 2008. DNA samples from 616 case-parental triads affected by CTDs and 1645 control-parental triads were genotyped using an Illumina® Golden Gate custom SNP panel. A hybrid design analysis, optimizing data from case and control trios, was used to identify maternal and fetal SNPs associated with CTDs RESULTS: Among 921 SNPs, 17 maternal and 17 fetal SNPs had a Bayesian false-discovery probability of <0.8. Ten of the 17 maternal SNPs and 2 of the 17 fetal SNPs were found within the glutamate-cysteine ligase, catalytic subunit (GCLC) gene. Fetal SNPs with the lowest Bayesian false-discovery probability (rs2612101, rs2847607, rs2847326, rs2847324) were found within the thymidylate synthetase (TYMS) gene. Additional analyses indicated that the risk of CTDs associated with candidate SNPs was modified by periconceptional folic acid supplementation. Nineteen maternal and nine fetal SNPs had a Bayesian false-discovery probability <0.8 for gene-by-environment (G × E) interactions with maternal folic acid supplementation. CONCLUSION: These results support previous studies suggesting that maternal and fetal SNPs within folate, homocysteine, and transsulfuration pathways are associated with CTD risk. Maternal use of supplements containing folic acid may modify the impact of SNPs on the developing heart.

New drug-like small molecule antagonizes phosphatidylinositol (3,4,5)-trisphosphate (PIP3) in patients with conotruncal heart defects.

Objectives: Conotruncal heart defects (CTDs) are highly heritable, and approximately one-third of all congenital heart defects are due to CTDs. Through post-analysis of GWAS data relevant to CTDs, a new putative signal transduction pathway, called Vars2-Pic3ca-Akt, associated with CTD has been hypothesized. Here, we aimed to validate the Vars2-Pic3ca-Akt pathway experimentally by measuring Vars2 and PIP3 in patients with CTDs and controls, and to construct a PIP3 inhibitor, as one of harmful-relevant CTD pathogenesis, through an Akt-based drug design strategy. Methods: rs2517582 genotype and relative Vars2 expression in 207 individuals were determined by DNA sequencing and qPCR respectively, and free plasma PIP3 in 190 individuals was quantified through ELISA. An Akt-pharmacophore feature model was used to discover PIP3 antagonists with multiple computational and drug-like estimation tools. Results: CTD pathogenesis due to Vars2-Pic3ca-Akt overstimulation was confirmed by elevated Vars2 and PIP3 in patients with CTDs. We identified a new small molecule, 322PESB, that antagonizes PIP3 binding. This molecule was prioritized via virtual screening of 21 hypothetical small molecules and it showed minimal RMSD change, high binding affinity andlower dissociation constant than PIP3-Akt complex by 1.99 Kcal/Mol, thus resulting in an equilibrium shift toward 322PESB-Akt complex formation. Moreover, 322PESB exhibited acceptable pharmacokinetics and drug likeness features according to ADME and Lipinski's rule of five classifiers. This compound is the first potential drug-like molecule reported for patients with CTDs with elevated PIP3. Conclusion: PIP3 is a useful diagnostic biomarker for patients with CTDs. The Akt-pharmacophore feature model is a feasible approach for discovery of PIP3 signalling antagonists. Further 322PESB development and testing are recommended.

Placental DNA Methylation Abnormalities in Prenatal Conotruncal Heart Defects.

Objective: This study aims to characterize the abnormal changes in placental DNA methylation associated with conotruncal heart defects (CTDs) and the level of methylation as epigenetic biomarkers for CTDs detection. Methods: This was a prospective study involving 28 fetuses diagnosed with CTDs in the second trimester at Beijing Anzhen Hospital between September 2020 and June 2021. These cases were classified into four groups based on their subtypes. 12 normal fetuses were used as controls. Placental tissue was obtained after inducing labor in fetuses. To identify differential methylation sites (DMSs) and regions (DMRs) in cases vs. controls, an Infinium Human Methylation 850 k bead chip was used. Differential methylation was assessed by comparing the ß-values for individual CpG loci. Based on the p-value (<0.05), the most discriminating CpG sites were identified. The area under the receiver-operating-characteristics curve (AUC) was used to determine the predictive accuracy of CpG loci with significant methylation changes for CTDs. The function of genes was assessed through KEGG enrichment analysis, Gene Ontology (GO) analysis, and KEGG pathway analysis. Results: In comparison to the control group, the DNA methylation of the placental tissue is significantly different in fetuses with CTDs. We identified the most significantly different methylated loci and they demonstrated excellent individual predictive accuracy for CTDs detection with AUC >0.9 in cases compared with controls. HOXD9, CNN1, NOTCH1, and ECE1 were identified as CTDs-detection candidate genes. Conclusion Our study established the abnormal changes in placental methylation associated with CTDs and potential epigenetic biomarkers for CTDs detection.

22q11.2 Deletion Syndrome: Impact of Genetics in the Treatment of Conotruncal Heart Defects.

Congenital heart diseases represent one of the hallmarks of 22q11.2 deletion syndrome. In particular, conotruncal heart defects are the most frequent cardiac malformations and are often associated with other specific additional cardiovascular anomalies. These findings, together with extracardiac manifestations, may affect perioperative management and influence clinical and surgical outcome. Over the past decades, advances in genetic and clinical diagnosis and surgical treatment have led to increased survival of these patients and to progressive improvements in postoperative outcome. Several studies have investigated long-term follow-up and results of cardiac surgery in this syndrome. The aim of our review is to examine the current literature data regarding cardiac outcome and surgical prognosis of patients with 22q11.2 deletion syndrome. We thoroughly evaluate the most frequent conotruncal heart defects associated with this syndrome, such as tetralogy of Fallot, pulmonary atresia with major aortopulmonary collateral arteries, aortic arch interruption, and truncus arteriosus, highlighting the impact of genetic aspects, comorbidities, and anatomical features on cardiac surgical treatment.