Congenital heart defects (CHDs) have had an increasing prevalence over the last decades, being one of the most common congenital defects. Their etiopathogenesis is multifactorial in origin. About 10–15% of all CHD can be attributed to copy number variations (CNVs), a type of submicroscopic structural genetic alterations. The aim of this study was to evaluate the involvement of CNVs in the development of congenital heart defects. We performed a cohort study investigating the presence of CNVs in the 22q11.2 region and GATA4, TBX5, NKX2-5, BMP4, and CRELD1 genes in patients with syndromic and isolated CHDs. A total of 56 patients were included in the study, half of them (28 subjects) being classified as syndromic. The most common heart defect in our study population was ventricular septal defect (VSD) at 39.28%. There were no statistically significant differences between the two groups in terms of CHD-type distribution, demographical, and clinical features, with the exceptions of birth length, weight, and length at the time of blood sampling, that were significantly lower in the syndromic group. Through multiplex ligation-dependent probe amplification (MLPA) analysis, we found two heterozygous deletions in the 22q11.2 region, both in patients from the syndromic group. No CNVs involving GATA4, NKX2-5, TBX5, BMP4, and CRELD1 genes were identified in our study. We conclude that the MLPA assay may be used as a first genetic test in patients with syndromic CHD and that the 22q11.2 region may be included in the panels used for screening these patients.

Background: Noonan syndrome (NS) is a genetically heterogeneous condition within the RASopathies spectrum, with distinctive craniofacial features, congenital heart defects, short stature, and variably present developmental delay. Most cases result from variants in genes regulating the RAS/MAPK pathway, with PTPN11 variants being the most frequent; the c.922A>G substitution being among the most commonly reported. Methods: This pilot study analyzed clinical and partial genetic features of NS in a cohort from Transylvania, evaluated in the Children’s Emergency Clinical Hospital in Cluj-Napoca. Thirty-one patients fulfilling the Van der Burgt diagnostic criteria (twenty-two males, nine females) were included. Clinical data were systematically reviewed, and targeted molecular testing for the PTPN11 c.922A>G variant was performed. Results: Congenital heart defects were highly prevalent, with pulmonary stenosis representing the most frequent anomaly (54.8%). Craniofacial dysmorphism was observed in 76.7% of cases, cryptorchidism in 50% of the males, and short stature below the third percentile was described in 77.4% of patients. Genetic screening identified the PTPN11 c.922A>G variant in two individuals (6.45%). Additional diagnoses included Williams–Beuren syndrome and a 17q11.2 deletion consistent with Neurofibromatosis–Noonan syndrome, underscoring the clinical and genetic heterogeneity of the cohort. Comparison with international reports highlighted variability in phenotype and variant frequency. Future research directions include Sanger sequencing of key PTPN11 exons and the application of next-generation sequencing targeting all RAS pathway genes. Conclusions: This is the first Romanian cohort study on patients with a clinical suspicion of NS, providing insight into their evaluation. The findings reinforce the need for comprehensive molecular approaches, facilitating diagnostic precision and counseling strategies.

Background: RASopathies represent a clinically and genetically diverse group of syndromes resulting from germline mutations in genes regulating the RAS/mitogen-activated protein kinase (MAPK) signaling cascade. Methods: The aim of this study was to describe the clinical features and genetic variants identified in patients with genetically confirmed Noonan syndrome (NS) in a limited cohort from Romania. A total of 25 patients with positive genetic testing for NS-associated genes were included. Genetic testing was performed primarily using next-generation sequencing. Results: A total of twenty-six variants were identified in twenty-five patients, as one patient carried two pathogenic variants in the PTPN11 gene (c.188A>G and c.922A>G). Of these variants, twenty-four (92.31%) were classified as pathogenic and two (7.69%) as variants of uncertain significance (VUS). Pathogenic variants were found in different genes, including PTPN11, LZTR1, SOS1, and RAF1, with PTPN11 being the most frequently affected gene. Males predominated (17/25), with a male-to-female ratio of approximately 2:1. Two patients inherited the pathogenic variant from an affected parent. Cardiovascular involvement was present in 21 patients (84%), with pulmonary valve stenosis (PVS) being the most common finding (48%), followed by hypertrophic cardiomyopathy (16%). Additional cardiac anomalies included atrial septal defect, valvular regurgitation, dysplastic valves, coarctation of the aorta, and sinotubular junction narrowing. Short stature was observed in 64% of patients, and craniofacial dysmorphism was present in 96%. Cutaneous, ectodermal, dental, ophthalmologic, and auditory manifestations were variably observed. Conclusions: Although based on a limited cohort from Romania, this study provides insights into clinical features suggestive of NS. Our findings highlight the genetic heterogeneity of NS and emphasize the importance of comprehensive genetic testing for confirming diagnosis, guiding clinical management, and supporting family counseling.