Genotype-phenotype Correlation Research Articles

Genotype Phenotype Correlation of Renal Tumors in the Cancer Genome Atlas Database.

Morphological features are critical in evaluation of renal tumors and directing molecular workup. The objective of this study was to review histomorphology of renal tumors with molecular alterations of known subtypes. Renal tumors in The Cancer Genome Atlas were reviewed to identify tumors with defining molecular alterations. Single representative digital slides and pathology reports were reviewed and morphologic features recorded. Sixty tumors were identified with molecular alterations in genes characteristic of defined renal cell carcinoma (RCC) subtypes. Findings included the presence of both low- and high-grade histology in TFE3 rearranged RCCs, TFEB amplified RCCs, succinate dehydrogenase (SDH) mutated RCCs and RCCs with mutations in mismatch repair genes. Three ELOC mutated RCCs were identified, one of which demonstrated infiltrative features. Pseudostratification of nuclei in fumarate hydratase mutated RCCs and nuclear grooves in SDH mutated RCCs were intriguing findings not previously reported. Mucinous features were noted in NF2, KRAS, and SDH mutated and ALK rearranged tumors. Significant morphologic overlap was noted across most categories with limited clues for subclassification. Whereas the number of diagnostic entities for kidney tumors continues to increase, many of these have overlapping features, highlighting the significant role molecular characterization currently plays and will continue to play in the future.

Comment on Maghsoudlou et al. Titled “Uveitis Associated with Monogenic Autoinflammatory Syndromes in Children”

ABSTRACT The work by Maghsoudlou et al. provides a comprehensive examination of monogenic autoinflammatory syndromes (MAIS) in children, with a specific focus on uveitis as a significant clinical manifestation. It meticulously details the genetic underpinnings, clinical features, diagnostic criteria, and current therapeutic strategies, including the use of biologics. This critique highlights the strengths of the review and suggests further exploration in areas such as long-term treatment outcomes, genotype-phenotype correlations, and the impact of MAIS on quality of life. Future research could benefit from longitudinal studies and enhanced predictive models to improve management and treatment personalization.

High-resolution diffusion magnetic resonance imaging and spatial-transcriptomic in developing mouse brain

Brain development is a highly complex process regulated by numerous genes at the molecular and cellular levels. Brain tissue exhibits serial microstructural changes during the development process. High-resolution diffusion magnetic resonance imaging (dMRI) affords a unique opportunity to probe these changes in the developing brain non-destructively. In this study, we acquired multi-shell dMRI datasets at 32 µm isotropic resolution to investigate the tissue microstructure alterations, which we believe to be the highest spatial resolution dMRI datasets obtained for postnatal mouse brains. We adapted the Allen Developing Mouse Brain Atlas (ADMBA) to integrate quantitative MRI metrics and spatial transcriptomics. Diffusion tensor imaging (DTI), diffusion kurtosis imaging (DKI), and neurite orientation dispersion and density imaging (NODDI) metrics were used to quantify brain development at different postnatal days. We demonstrated that the differential evolutions of fiber orientation distributions contribute to the distinct development patterns in white matter (WM) and gray matter (GM). Furthermore, the genes enriched in the nervous system that regulate brain structure and function were expressed in spatial correlation with age-matched dMRI. This study is the first one providing high-resolution dMRI, including DTI, DKI, and NODDI models, to trace mouse brain microstructural changes in WM and GM during postnatal development. This study also highlighted the genotype-phenotype correlation of spatial transcriptomics and dMRI, which may improve our understanding of brain microstructure changes at the molecular level.

Cohort Expansion and Genotype-Phenotype Analysis of RAB11A-Associated Neurodevelopmental Disorder

BackgroundGTPases of the Rab family are important orchestrators of membrane trafficking, and their dysregulation has been linked to a variety of neuropathologies. In 2017, we established a causal link between RAB11A variants and developmental and epileptic encephalopathy. In this study, we expand the phenotype of RAB11A-associated neurodevelopmental disorder and explore genotype-phenotype correlations. MethodsWe assessed 16 patients with pathogenic or likely pathogenic RAB11A variants, generally de novo, heterozygous missense variants. One individual had a homozygous nonsense variant, although concomitant with a pathogenic LAMA2 variant, which made their respective contributions to the phenotype difficult to discriminate. ResultsWe reinforce the finding that certain RAB11A missense variants lead to intellectual disability and developmental delays. Other clinical features might include gait disturbances, hypotonia, magnetic resonance imaging abnormalities, visual anomalies, dysmorphisms, early adrenarche, and obesity. Epilepsy seems to be less common and linked to variants outside the binding sites. Individuals with variants in the binding sites seem to have a more multisystemic, nonepileptic phenotype. ConclusionsSimilar to other Rab-related disorders, RAB11A-associated neurodevelopmental disorder can also impact gait, tonus, brain anatomy and physiology, vision, adrenarche, and body weight and structure. Epilepsy seems to affect the minority of patients with variants outside the binding sites.

Novel causative variants in Legius syndrome: SPRED1 Genotype spectrum expansion.

Legius syndrome, commonly referred to as SPRED1-related neurofibromatosis type 1-like syndrome, is a rare autosomal dominant disorder characterized by café-au-lait macules, freckling, lipomas, macrocephaly, and heterogeneous neurodevelopmental manifestations, including a different degree of learning difficulties. Although a partial clinical overlap exists with neurofibromatosis type 1 (NF1), Legius syndrome is distinguished by its genetic etiology and the absence of neurofibromas, indicating an inherent lack of tumor risk. The SPRED1 gene encodes the Sprouty-related protein with an EVH1 domain 1 (SPRED1), a negative regulator of the RAS-MAPK signaling pathway with a crucial role in cellular growth and development. Despite various genetic variants and genomic deletions associated with Legius syndrome, the full genetic spectrum of this condition remains elusive. In this study, we investigated the underlying genetic etiology in a cohort of patients presenting with typical manifestations of Legius syndrome using a custom Next Generation Sequencing (NGS) panel and Multiplex Ligation-Dependent Probe Amplification (MLPA) for NF1 and SPRED1. We identified 12 novel SPRED1 damaging variants segregating with the phenotype in all families. These rare variants affect conserved residues of the protein and are predicted damaging according to in silico tools. No clear genotype-phenotype correlations could be observed in the current cohort and previously reported patients, underscoring the heterogeneous genotype spectrum of this condition. Our findings expand the understanding of SPRED1 variants causing Legius syndrome and underscore the importance of comprehensively characterizing the genetic landscape of this disorder. Despite the absence of clear genotype-phenotype correlations, elucidating the genetic etiology of Legius syndrome is pertinent for facilitating accurate diagnosis, genetic counseling, and therapeutic interventions.

Novel Cases of Non-Syndromic Hearing Impairment Caused by Pathogenic Variants in Genes Encoding Mitochondrial Aminoacyl-tRNA Synthetases.

Dysfunction of some mitochondrial aminoacyl-tRNA synthetases (encoded by the KARS1, HARS2, LARS2 and NARS2 genes) results in a great variety of phenotypes ranging from non-syndromic hearing impairment (NSHI) to very complex syndromes, with a predominance of neurological signs. The diversity of roles that are played by these moonlighting enzymes and the fact that most pathogenic variants are missense and affect different domains of these proteins in diverse compound heterozygous combinations make it difficult to establish genotype-phenotype correlations. We used a targeted gene-sequencing panel to investigate the presence of pathogenic variants in those four genes in cohorts of 175 Spanish and 18 Colombian familial cases with non-DFNB1 autosomal recessive NSHI. Disease-associated variants were found in five cases. Five mutations were novel as follows: c.766C>T in KARS1, c.475C>T, c.728A>C and c.1012G>A in HARS2, and c.795A>G in LARS2. We provide audiograms from patients at different ages to document the evolution of the hearing loss, which is mostly prelingual and progresses from moderate/severe to profound, the middle frequencies being more severely affected. No additional clinical sign was observed in any affected subject. Our results confirm the involvement of KARS1 in DFNB89 NSHI, for which until now there was limited evidence.

Prenatal diagnosis of a 15q24.1 microdeletion in a fetus with cerebral and urogenital abnormalities.

15q24.1 microdeletion syndrome is a recently described condition often resulting from non-allelic homologous recombination (NAHR). Typical clinical features include pre and post-natal growth retardation, facial dysmorphism, developmental delay and intellectual disability. Nonspecific urogenital, skeletal, and digit abnormalities may be present, although other congenital malformations are less frequent. Consequently, only one case was reported prenatally, complicating the genotype-phenotype correlation and the genetic counseling. We identified prenatally a second case, presenting with cerebral abnormalities including hydrocephaly, macrocephaly, cerebellum hypoplasia, vermis hypoplasia, rhombencephalosynapsis, right kidney agenesis with left kidney duplication and micropenis. Genome-wide aCGH assay allowed a diagnosis at 26 weeks of amenorrhea revealing a 1.6 Mb interstitial deletion on the long arm of chromosome 15 at 15q24.1-q24.2 (arr[GRCh37] 15q24.1q24.2(74,399,112_76,019,966)x1). A deep review of the literature was undertaken to further delineate the prenatal clinical features and the candidate genes involved in the phenotype. Cerebral malformations are typically nonspecific, but microcephaly appears to be the most frequent in postnatal cases. Our case is the first reported with a frank cerebellar involvement.

Reviewing hereditary connective tissue disorders: Proposals of harmonic medicolegal assessments.

Hereditary connective tissue disorders (HCTDs) are a heterogeneous group of inherited diseases. These disorders show genetic mutations with loss of function of primary components of connective tissue, such as collagen and elastic fibers. There are more than 200 conditions that involve hereditary connective tissue disorders, while the most known are Marfan syndrome, Osteogenesis Imperfecta, and Ehlers-Danlos syndromes. These disorders need continuous updates, multidisciplinary skills, and specific methodologic evaluations sharing many medicolegal issues. Marfan syndrome and Ehlers-Danlos syndromes show a high risk of early sudden death. As a consequence of this, postmortem genetic testing can identify novel genotype-phenotype correlations which help the clinicians to assess personalized cardiovascular screening programs among the ill subjects. Genetic testing is also essential to identify children suffering from Osteogenesis Imperfecta, especially when a physical abuse is clinically suspected. However, this is a well-known clinical problem even though there are still challenges to interpret genetic data and variants of unknown significance due to the current extensive use of new genetic/genomic techniques. Additionally, the more significant applications and complexities of genomic testing raise novel responsibilities on the clinicians, geneticists, and forensic practitioners as well, increasing potential liability and medical malpractice claims. This systematic review provides a detailed overview on how multidisciplinary skills belonging to clinicians, medicolegal consultants, radiologists, and geneticists can cooperate to manage HCTDs from autopsy or clinical findings to genetic testing. Thus, technical aspects need to be addressed to the medicolegal community since there is no consensus works or guidelines which specifically discuss these issues.

Identification of distinct genotypes in circulating RSV A strains based on variants in the virus replication-associated genes.

Respiratory syncytial virus (RSV) is a common cause of respiratory infection that often leads to hospitalization of infected younger children and older adults. RSV is classified into two strains, A and B, each with several subgroups or genotypes. One issue with the definition of these subgroups is the lack of a unified method of identification or genotyping. We propose that genotyping strategies based on the genes coding for replication-associated proteins could provide critical information on the replication capacity of the distinct subgroups, while clearly distinguishing genotypes. Here, we analyzed the virus replication-associated genes N, P, M2, and L from de novo assembled RSV A sequences obtained from 31 newly sequenced samples from hospitalized patients in Philadelphia and 78 additional publicly available sequences from different geographic locations within the United States. In-depth analysis and annotation of variants in the replication-associated proteins identified the polymerase protein L as a robust target for genotyping RSV subgroups. Importantly, our analysis revealed non-synonymous variations in L that were consistently accompanied by conserved changes in its co-factor P or the M2-2 protein, suggesting associations and interactions between specific domains of these proteins. Similar associations were seen among sequences of the related human metapneumovirus. These results highlight L as an alternative to other RSV genotyping targets and demonstrate the value of in-depth analyses and annotations of RSV sequences as it can serve as a foundation for subsequent in vitro and clinical studies on the efficiency of the polymerase and fitness of different virus isolates.IMPORTANCEGiven the historical heterogeneity of respiratory syncytial virus (RSV) and the disease it causes, there is a need to understand the properties of the circulating RSV strains each season. This information would benefit from an informative and consensus method of genotyping the virus. Here, we carried out a variant analysis that shows a pattern of specific variations among the replication-associated genes of RSV A across different seasons. Interestingly, these variation patterns, which were also seen in human metapneumovirus sequences, point to previously defined interactions of domains within these genes, suggesting co-variation in the replication-associated genes. Our results also suggest a genotyping strategy that can prove to be particularly important in understanding the genotype-phenotype correlation in the era of RSV vaccination, where selective pressure on the virus to evolve is anticipated. More importantly, the categorization of pneumoviruses based on these patterns may be of prognostic value.

Characterization of 13 Novel Genetic Variants in Genes Associated with Epilepsy: Implications for Targeted Therapeutic Strategies.

Childhood epilepsies are caused by heterogeneous underlying disorders where approximately 40% of the origins of epilepsy can be attributed to genetic factors. The application of next-generation sequencing (NGS)has revolutionized molecular diagnostics and has enabled the identification of disease-causing genes and variants in childhood epilepsies.The objective of this study was to use NGS to identify variants in patients with childhood epilepsy, to expand the variant spectrum and discover potential therapeutic targets. In our study, 55 children with epilepsy of unknown etiology were analyzed bycombining clinical-exome and whole-exome sequencing. Novel variants were characterized using various in silico algorithms for pathogenicity and structure prediction. The molecular genetic cause of epilepsy was identified in 28 patients and the overall diagnostic success rate was 50.9%. We identified variants in 22 different genes associated with epilepsy that correlate well with the described phenotype. SCN1A gene variants were found in five unrelated patients, while ALDH7A1 and KCNQ2 gene variants were found twice. In the other 19 genes, variants were found only in a single patient. This includes genes such as ASH1L, CSNK2B, RHOBTB2, and SLC13A5, which have only recently been associated with epilepsy. Almost half of diagnosed patients (46.4%) carried novel variants. Interestingly, we identified variants in ALDH7A1, KCNQ2, PNPO, SCN1A, and SCN2A resulting ingene-directed therapy decisions for 11 children from our study, including four children who all carried novel SCN1A genetic variants. Described novel variants will contribute to a better understanding of the European genetic landscape, while insights into the genotype-phenotype correlation will contribute to a better understanding of childhood epilepsies worldwide. Given the expansion of molecular-based approaches, each newly identified genetic variant could become a potential therapeutic target.

A review of the genetic background in complicated WT1-related disorders.

The Wilms tumor 1 (WT1) gene was first identified in 1990 as a strong candidate for conferring a predisposition to Wilms tumor. The WT1 protein has four zinc finger structures (DNA binding domain) at the C-terminus, which bind to transcriptional regulatory sequences on DNA, and acts as a transcription factor. WT1 is expressed during kidney development and regulates differentiation, and is also expressed in glomerular epithelial cells after birth to maintain the structure of podocytes. WT1-related disorders are a group of conditions associated with an aberrant or absent copy of the WT1 gene. This group of conditions encompasses a wide phenotypic spectrum that includes Denys-Drash syndrome (DDS), Frasier syndrome (FS), Wilms-aniridia-genitourinary-mental retardation syndrome, and isolated manifestations of nephropathy or Wilms tumor. The genotype-phenotype correlation is becoming clearer: patients with missense variants in DNA binding sites including C2H2 sites manifest DDS and develop early-onset and rapidly developing end-stage kidney disease. A deeper understanding of the genotype-phenotype correlation has also been obtained in DDS, but no such correlation has been observed in FS. The incidence of Wilms tumor is higher in patients with DDS and exon-truncating variants than in those with non-truncating variants. Here, we briefly describe the genetic background of this highly complicated WT1-related disorders.

Myhre syndrome in adulthood: clinical variability and emerging genotype-phenotype correlations.

Myhre syndrome (MS, MIM 139210) is a rare multisystemic disorder caused by recurrent pathogenic missense variants in SMAD4. The clinical features have been mainly documented in childhood and comprise variable neurocognitive development, recognizable craniofacial features, a short stature with a pseudo-muscular build, hearing loss, thickened skin, joint limitations, diverse cardiovascular and airway manifestations, and increased fibrosis often following trauma or surgery. In contrast, adults with MS are underreported obscuring potential clinical variability. Here, we describe 24 adults with MS, including 17 diagnosed after the age of 18 years old, and we review the literature on adults with MS. Overall, our cohort shows a milder phenotype as well as lower mortality rates compared to what has been published in literature. Individuals with a codon 500 variant in SMAD4 present with a more pronounced neurodevelopmental and systemic phenotype. However, in contrast to the literature, we observe cardiovascular abnormalities in individuals with the p.(Arg496Cys) variant. In addition, we describe scoliosis as a new manifestation and we report fertility in two additional males with the p.(Arg496Cys). In conclusion, our study contributes novel insights into the clinical variability of MS and underscores the importance of variant-specific considerations, and we provide recommendations for the management of MS in adulthood.

Distinct neurodevelopmental and epileptic phenotypes associated with gain- and loss-of-function GABRB2 variants

Variants in GABRB2, encoding the β2 subunit of the γ-aminobutyric acid type A (GABAA) receptor, can result in a diverse range of conditions, ranging from febrile seizures to severe developmental and epileptic encephalopathies. However, the mechanisms underlying the risk of developing milder vs more severe forms of disorder remain unclear. In this study, we conducted a comprehensive genotype-phenotype correlation analysis in a cohort of individuals with GABRB2 variants. Genetic and electroclinical data of 42 individuals harbouring 26 different GABRB2 variants were collected and accompanied by electrophysiological analysis of the effects of the variants on receptor function. Electrophysiological assessments of α1β2γ2 receptors revealed that 25/26 variants caused dysfunction to core receptor properties such as GABA sensitivity. Of these, 17 resulted in gain-of-function (GOF) while eight yielded loss-of-function traits (LOF). Genotype-phenotype correlation analysis revealed that individuals harbouring GOF variants suffered from severe developmental delay/intellectual disability (DD/ID, 74%), movement disorders such as dystonia or dyskinesia (59%), microcephaly (50%) and high risk of early mortality (26%). Conversely, LOF variants were associated with milder disease manifestations. Individuals with these variants typically exhibited fever-triggered seizures (92%), milder degrees of DD/ID (85%), and maintained ambulatory function (85%). Notably, severe movement disorders or microcephaly were not reported in individuals with loss-of-function variants. The data reveals that genetic variants in GABRB2 can lead to both gain and loss-of-function, and this divergence is correlated with distinct disease manifestations. Utilising this information, we constructed a diagnostic flowchart that aids in predicting the pathogenicity of recently identified variants by considering clinical phenotypes. This work was funded by the Australian National Health & Medical Research Council, the Novo Nordisk Foundation and The Lundbeck Foundation.

Investigation of patients with childhood epilepsy in single center: Comprehensive genetic testing experience.

Epilepsy is a common multifactorial neurological disease usually diagnosed during childhood. In this study, we present the contribution of consecutive genetic testing to the genetic diagnostic yield of childhood epilepsy. In 100 children (53 female, 47 male) with epilepsy, targeted sequencing (TS) and clinical exome sequencing (CES) were performed. All cases (n= 100) included in the study were epilepsy patients. In addition, we investigated the genetic diagnosis rates according to the associated co-occurring findings (including developmental delay/intellectual disability, brain malformations, macro-/microcephaly, and dysmorphic features). The overall diagnostic rate in this study was 33% (n= 33 patients). We identified 11 novel variants in WDR45, ARX, PCDH19, SCN1A, CACNA1A, LGI1, ASPM, MECP2, NF1, TSC2, and CDK13. Genetic diagnosis rates were as follows: cases with developmental delay/intellectual disability 38.7% (24/62) and without developmental delay/intellectual disability 23.6% (9/38); cases with brain malformations 46.8% (15/32) and without brain malformations 25% (16/64); cases with macro-/microcephaly 50% (6/12) and without macro-/microcephaly 28.4% (25/88); and cases with dysmorphic features 48.2% (14/29) and without dysmorphic features 23.9% (17/71). Genotype-phenotype correlation is even more important in diseases such as epilepsy, which include many genes and variants of these genes in etiopathogenesis. We presented the clinical findings of the cases carrying 11 novel variants in detail, including dysmorphic features, accompanying neurodevelopmental disorders, EEG results, and brain MRI results.

A Novel Missense Heterozygous Mutation in NKX2-5 Gene in a Family with Congenital Septal Defects and Cardiomyopathy: Case Series and Literature Review

AbstractSingle-gene mutations are important causes of congenital heart defects in children. Mutations in the NKX2-5 gene have been recently described in the literature as a cause of septal defects and cardiomyopathy. However, the spectrum of cardiac disease associated with NKX2-5 gene mutations is variable, ranging from asymptomatic septal defects to cardiomyopathy and sudden death. In this case report, we describe a case of 2-year-old child, along with two other family members, with a novel missense heterozygous (c.544G > T p.[Val182Phe]) mutation in NKX2-5 gene consistent with the diagnosis of autosomal dominant atrial septal defects with cardiomyopathy. This report can contribute to the understanding of genotype–phenotype correlations; it emphasizes the significant clinical relevance of NKX2-5 gene defects for congenital heart defects, sudden death, and cardiomyopathy, especially in multiple affected family members. It also suggests that individuals with NKX2-5 mutations are at risk of lethal arrhythmias and conduction disorders, that is why they should be evaluated routinely to assess the need for implantable cardioverter-defibrillator or pacemaker implantation.

A Rare Coincidence of Three Inherited Diseases in a Family with Cardiomyopathy and Multiple Extracardiac Abnormalities.

A genetic diagnosis of primary cardiomyopathies can be a long-unmet need in patients with complex phenotypes. We investigated a three-generation family with cardiomyopathy and various extracardiac abnormalities that had long sought a precise diagnosis. The 41-year-old proband had hypertrophic cardiomyopathy (HCM), left ventricular noncompaction, myocardial fibrosis, arrhythmias, and a short stature. His sister showed HCM, myocardial hypertrabeculation and fibrosis, sensorineural deafness, and congenital genitourinary malformations. Their father had left ventricular hypertrophy (LVH). The proband's eldest daughter demonstrated developmental delay and seizures. We performed a clinical examination and whole-exome sequencing for all available family members. All patients with HCM/LVH shared a c.4411-2A>C variant in ALPK3, a recently known HCM-causative gene. Functional studies confirmed that this variant alters ALPK3 canonical splicing. Due to extracardiac symptoms in the female patients, we continued the search and found two additional single-gene disorders. The proband's sister had a p.Trp329Gly missense in GATA3, linked to hypoparathyroidism, sensorineural deafness, and renal dysplasia; his daughter had a p.Ser251del in WDR45, associated with beta-propeller protein-associated neurodegeneration. This unique case of three monogenic disorders in one family shows how a comprehensive approach with thorough phenotyping and extensive genetic testing of all symptomatic individuals provides precise diagnoses and appropriate follow-up, embodying the concept of personalized medicine. We also present the first example of a splicing functional study for ALPK3 and describe the genotype-phenotype correlations in cardiomyopathy.

Genetics of hypertrophic cardiomyopathy: established and emerging implications for clinical practice.

Pathogenic variation in genes encoding proteins of the cardiac sarcomere is responsible for 30%-40% of cases of hypertrophic cardiomyopathy. The main clinical utility of genetic testing is to provide diagnostic confirmation and facilitation of family screening. It also assists in the detection of aetiologies, which require distinct monitoring and treatment approaches. Other clinical applications, including the use of genetic information to inform risk prediction models, have been limited by the challenge of establishing robust genotype-phenotype correlations with actionable consequences, but new data on the interaction between rare and common genetic variation, as well as the emergence of therapies targeting disease-specific pathogenic mechanisms, herald a new era for genetic testing in routine practice.

F8 variants and their genotype-phenotype correlations in Thai patients with haemophilia A: a nationwide multicentre study

AimsAnalysis of the F8 gene helps predict the risk of developing factor VIII (FVIII) inhibitors and the depth of phenotype in haemophilia A (HA) patients. Since data in Southeast Asian...

Delineation of the phenotypes and genotypes of PIK3CA-related overgrowth spectrum in East asians.

PIK3CA-related overgrowth spectrum (PROS) is an umbrella term to describe a diverse range of developmental disorders. Research to date has predominantly emerged from Europe and North America, resulting in a notable scarcity of studies focusing on East Asian populations. Currently, the prevalence and distribution of PIK3CA variants across various genetic loci and their correlation with distinct phenotypes in East Asian populations remain unclear. This study aims to elucidate the phenotype-genotype correlations of PROS in East Asian populations. We presented the phenotypes and genotypes of 82 Chinese patients. Among our cohort, 67 individuals carried PIK3CA variants, including missense, frameshift, and splice variants. Six patients presented with both PIK3CA and an additional variant. Seven PIK3CA-negative patients exhibited overlapping PROS manifestations with variants in GNAQ, AKT1, PTEN, MAP3K3, GNA11, or KRAS. An integrative review of the literature pertaining to East Asian populations revealed that specific variants are uniquely associated with certain PROS phenotypes. Some rare variants were exclusively identified in cases of megalencephaly and diffuse capillary malformation with overgrowth. Non-hotspot variants with undefined oncogenicity were more common in CNS phenotypes. Diseases with vascular malformation were more likely to have variants in the helical domain, whereas phenotypes involving adipose/muscle overgrowth without vascular abnormalities predominantly presented variants in the C2 domain. Our findings underscore the unique phenotype-genotype patterns within the East Asian PROS population, highlighting the necessity for an expanded cohort to further elucidate these correlations. Such endeavors would significantly facilitate the development of PI3Kα selective inhibitors tailored for the East Asian population in the future.

Autistic traits in youth with familial adenomatous polyposis: A Dutch-Canadian case-control study.

This study investigated the neurodevelopmental impact of pathogenic adenomatous polyposis coli (APC) gene variants in patients with familial adenomatous polyposis (FAP), a cancer predisposition syndrome. We hypothesized that certain pathogenic APC variants result in behavioral-cognitive challenges. We compared 66 FAP patients (cases) and 34 unaffected siblings (controls) to explore associations between APC variants and behavioral and cognitive challenges. Our findings indicate that FAP patients exhibited higher Social Responsiveness Scale (SRS) scores, suggesting a greater prevalence of autistic traits when compared to unaffected siblings (mean 53.8 vs. 47.4, Wilcoxon p = 0.018). The distribution of SRS scores in cases suggested a bimodal pattern, potentially linked to the location of the APC variant, with scores increasing from the 5' to 3' end of the gene (Pearson's r = 0.33, p = 0.022). While we observed a trend toward lower educational attainment in cases, this difference was not statistically significant. This study is the first to explore the connection between APC variant location and neurodevelopmental traits in FAP, expanding our understanding of the genotype-phenotype correlation. Our results emphasize the importance of clinical assessment for autistic traits in FAP patients, shedding light on the potential role of APC gene variants in these behavioral and cognitive challenges.