Search Results (1,079)

Background/Objectives: While ocular albinism (OA) is usually associated with reduced vision, nystagmus, and foveal hypoplasia, there is phenotypic variability in iris and fundus hypopigmentation. Hemizygous pathogenic/likely pathogenic (P/LP) variants in GPR143 at X: 151.56–151.59 have been shown in the literature to be associated with OA. The purpose of this study was to report the case of a Hispanic male with X-linked inherited OA associated with a hemizygous GPR143 variant and to review the literature relating to genotype–phenotype associations with GPR143 and OA. Methods: After consent to an IRB-approved protocol, a 14-year-old Hispanic male patient with OA and his parents underwent whole genome sequencing (WGS) in 2023. Two maternal uncles with nystagmus underwent targeted variant testing in 2024. A literature review of reported GPR143 variants was completed. Results: A male with reduced visual acuity, infantile-onset nystagmus, foveal hypoplasia, and iris hypopigmentation was identified to have the variant GPR143, c.455+3A>G, which was also present in his mother and two affected maternal uncles. This variant has been previously identified in other Hispanic patients of Mexican descent. Additionally, 127 variants were identified in the literature and reported to be associated with OA. All patients had reduced visual acuity (average 0.71 ± 0.23 logMAR), 99% had nystagmus, 97% foveal hypoplasia, 79% fundus hypopigmentation, and 71% iris hypopigmentation. Of those patients with reported optotype best corrected visual acuity (BCVA), eight (9%) had VA from 20/25 to 20/40, 24 (24%) had VA from 20/50 to 20/80, and 63 (67%) had VA from 20/100 to 20/200. The most frequent type of variant was missense (31%, n = 39). Frameshift and nonsense variants were associated with the lowest rates of iris hypopigmentation (50% [n = 11] and 44% [n = 8], respectively; p = 0.0068). Conclusions: This case represents phenotypic variability of GPR143-associated OA and highlights the importance of repeat genetic testing and independent analyses of test results for accurate variant classification, particularly in non-White and Hispanic patients. Further studies in more diverse populations are needed to better develop genotype–phenotype associations for GPR143-associated OA. Full article

Inherited epidermolysis bullosa (EB) is a heterogeneous clinical entity that includes over 30 phenotypically and/or genotypically distinct inherited disorders, characterized by mechanical skin fragility and bullae formation. Junctional EB (JEB) is an autosomal recessive disease characterized by an intermediated cleavage level within the skin layers, commonly at the “lamina lucida”. Laryngo-onycho-cutaneous syndrome (LOC) is an extremely rare variant of JEB, characterized by granulation tissue formation in specific body sites (skin, larynx, and nails). Although most cases of JEB are caused by pathogenic variants occurring in the genes encoding for classical components of the lamina lucida, such as laminin 332 (LAMA3, LAMB3, LAMC2), integrin α6β4 (ITGA6, ITGB4), and collagen XVII (COL17A1), other variants have also been described. We report the case of a 4-month-old male infant who presented with recurrent bullous and erosive lesions from the first month of life. At the first dermatological evaluation, the patient was agitated and exhibited hoarse breathing, a clinical sign suggestive of laryngeal involvement. Multiple polygonal skin erosions were observed on the cheeks, along with similar isolated, roundish lesions on the scalp and legs. Notably, nail dystrophy and near-complete anonychia were evident on the left first and fifth toes. Due to the coexistence of skin erosions and nail dystrophy in such a young infant, a congenital bullous disorder was suspected, prompting molecular analysis of all potentially involved genes. In the patient’s DNA, clinical exome sequencing (CES) identified a pathogenic variant, apparently in homozygosity, in the exon 1 of the LAMA3 gene (18q11.2; NM_000227.6): c.47G > A;p.Trp16*. The presence of this variant was confirmed, in heterozygosity, in the genomic DNA of the patient’s mother, while it was absent in the father’s DNA. Subsequently, trio-based SNP array analysis was performed, revealing a paternally derived pathogenic microdeletion encompassing the LAMA3 locus (18q11.2). To our knowledge, this is the first reported case of JEB with a LOC-like phenotype caused by a maternally inherited monoallelic nonsense mutation in LAMA3, unmasked by an almost complete deletion of the paternal allele. The combined use of exome sequencing and SNP array is proving essential for elucidating autosomal recessive diseases with a discordant segregation. This is pivotal for providing accurate genetic counseling to parents regarding future pregnancies. Full article

Background/Objectives: Pseudohypoparathyroidism (PHP) is a group of genetic disorders characterized by end-organ resistance to multiple hormones, short stature, brachydactyly, subcutaneous ossifications, obesity, and developmental delays. The tissue specific imprinting of GNAS in the hypothalamus may lead to different eating behavior phenotypes in maternally inherited (PHP1A, PHP1B) vs. paternally inherited (PPHP) variants. In this exploratory study, we aimed to evaluate differences in eating behaviors in a cohort of patients with PHP1A, PPHP and PHP1B. Methods: Assessments included caregiver-reported measures (hyperphagia questionnaire, children’s eating behavior questionnaire, child feeding questionnaire) and self-reported measures (three factor eating behavior questionnaire). Results: A total of 58 patients with PHP1A, 13 patients with PPHP and 10 patients with PHP1B contributed data, along with 124 obese pediatric controls. An increased risk of obesity was found in PHP1A vs. PPHP (adult body mass index (BMI) 39.8 ± 8.7 vs. 30.2 ± 7.4 kg/m², p = 0.03). Parents reported significantly earlier onset of interest in food in children with PHP1A (2.0 ± 2.3 years) and PHP1B (1.1 ± 1.3 years) compared with controls (5.2 ± 3.2 years, p < 0.001). Measures of hyperphagia, satiety and other feeding behaviors were all similar to controls. The highest hyperphagia questionnaire scores were seen prior to adolescence. In a multi-year, longitudinal assessment of 11 pediatric patients with PHP1A, hyperphagia scores were stable and 25% showed an improvement in symptoms. Conclusion: Patients with PHP1A/1B may have hyperphagia symptoms from a young age but they do not worsen over time. Patients may overeat when allowed access to food, but do not usually have disruptive food seeking behaviors. Early diagnosis can give clinicians the opportunity to provide anticipatory diagnosis on the increased risk of obesity in PHP1A/1B and need for scheduled meals and controlled portions. Further studies with larger cohorts are needed to confirm these findings. Full article

Background/Objectives: Genetic testing is important for diagnosing inherited retinal diseases (IRDs), but further evidence is needed on the utility of singleton genetic testing in an Australian cohort. Methods: A consecutive series of individuals with clinically diagnosed IRDs without prior genetic testing underwent commercial panel-based sequencing (Invitae or Blueprint Genetics), clinical assessment, and multimodal imaging. Retinal images were graded using the Human Phenotype Ontology terms. Binary logistic regression was used to evaluate clinical predictors of a positive molecular diagnosis. Results: Among 140 participants (mean age 49 ± 19 years), genetic testing was undertaken, on average, 23 ± 17 years after the initial clinical IRD diagnosis. Of the 60% who received a probable molecular diagnosis, 40% require further phase testing, highlighting the limitations of singleton genetic testing. USH2A, ABCA4, and RPGR were the most common encountered genes; 67% of the probably solved participants had causative genes with targeted experimental treatments in ongoing human clinical trials. Symptom onset before the age of 30 (OR = 3.06 [95% CI: 1.34–7.18]) and a positive IRD family history (OR = 2.87 [95% CI: 1.27–6.78]) were each associated with higher odds of receiving a molecular diagnosis. Diagnostic rates were comparable across retinal imaging phenotypes (atrophy and autofluorescence patterns in widespread IRD, and the extent of dystrophy in macular IRDs). Conclusions: In an Australian IRD population without prior genetic testing, commercial panels yielded higher diagnostic rates in individuals with IRD onset before the age of 30 and those with an IRD family history. Further research is needed to understand the genetic basis of IRDs, especially isolated and late-onset cases, to improve diagnosis and access to emerging therapies. Full article

Background and Clinical Significance: Inherited thrombocytopenia (IT) is a heterogeneous group of disorders caused by mutations in over 45 genes. Among these, ANKRD26-related thrombocytopenia (ANKRD26-RT) accounts for a notable subset and is associated with variable bleeding tendencies and an increased risk of myeloid malignancies. However, the extent of this oncogenic risk appears to vary between specific gene variants. Understanding the genotype–phenotype relationship is essential for patient counseling and management. This report presents a multigenerational family carrying the rare c.−118C > G variant in the 5′ untranslated region of ANKRD26, contributing to the discussion on variant-specific cancer predisposition. Case Presentation: Two sisters aged 57 and 60 presented with lifelong bleeding diathesis and moderate thrombocytopenia. Their symptoms included easy bruising, menorrhagia, and excessive postoperative bleeding. Genetic testing confirmed heterozygosity for the ANKRD26 c.−118C > G variant. Bone marrow analysis revealed abnormal megakaryopoiesis without evidence of dysplasia or somatic mutations. One sister underwent major surgery without complications when managed with prophylactic hemostatic therapy. Their family history included multiple female relatives with similar symptoms, although formal testing was limited. Notably, none of the affected individuals developed hematologic malignancy, and only one developed esophageal cancer, with no current evidence linking this variant to solid tumors. Conclusions: This case underscores the importance of distinguishing between ANKRD26 variants when assessing malignancy risk. While ANKRD26-RT is associated with myeloid neoplasms, the c.−118C > G variant may confer a lower oncogenic potential. Variant-specific risk stratification and genetic counseling are crucial for optimizing surveillance and avoiding unnecessary interventions in low-risk individuals. Full article

Fruit size is an important agronomic trait affecting the yield and commercial value of melon and a key trait selected for during domestication. In this study, two respective melon accessions (large-fruited M202008 and small-fruited M202009) were crossed, and developed biparental mapping populations of the F₂ generation (160 and 382 plants) were checked across two subsequent experimental years (2023 and 2024). The phenotypic characterization and genetic inheritance analysis showed that melon fruit size is modulated by quantitative genetics. Bulked segregant sequencing analysis (BSA-seq) identified a stable and effective quantitative trait locus (QTL, named Cmfs) controlling fruit size, localized to a 3.75 Mb region on chromosome 9. To better delineate the main-effect Cmfs locus, co-dominant polymorphic molecular markers were developed in this genetic interval, and genotyping was performed within the F₂ mapping populations grown across two years. QTL analysis of the phenotypic and genotypic datasets delimited the major-effect Cmfs locus interval for fruit length [2023: logarithm of odds (LOD) value = 6.16, 16.20% phenotypic variation explained (PVE); 2024: LOD = 5.44, 6.35% PVE] and fruit diameter (2023: LOD value = 5.48, 14.59% PVE; 2024: LOD = 6.22, 7.22% PVE) to 1.88 and 2.20 Mb intervals, respectively. The annotation analysis across the melon genome and comparison of resequencing data from the two parental lines led to the preliminary identification of MELO3C021600.1 (annotated as cytochrome P450 724B1) as a candidate gene related to melon fruit size. These results provide a better understanding for further fine mapping and functional gene analysis related to melon fruit size. Full article

In this study, we investigated the mitochondrial defects resulting from the deletion of GCN5, a lysine-acetyltransferase, in the yeast Saccharomyces cerevisiae. Gcn5 serves as the catalytic subunit of the SAGA acetylation complex and functions as an epigenetic regulator, primarily acetylating N-terminal lysine residues on histones H2B and H3 to modulate gene expression. The loss of GCN5 leads to mitochondrial abnormalities, including defects in mitochondrial morphology, a reduced mitochondrial DNA copy number, and defective mitochondrial inheritance due to the depolarization of actin filaments. These defects collectively trigger the activation of the mitophagy pathway. Interestingly, deleting CSN5, which encodes to Csn5/Rri1 (Csn5), the catalytic subunit of the COP9 signalosome complex, rescues the mitochondrial phenotypes observed in the gcn5Δ strain. Furthermore, these defects are suppressed by exogenous ergosterol supplementation, suggesting a link between the rescue effect mediated by CSN5 deletion and the regulatory role of Csn5 in the ergosterol biosynthetic pathway. Full article

Cardiomyopathies represent a heterogeneous group of myocardial disorders, traditionally classified by phenotype into hypertrophic, dilated, and arrhythmogenic. Historically, these conditions have been attributed to high-penetrance rare variants in key structural genes, consistent with a classical Mendelian pattern of inheritance. However, emerging evidence suggests that this model does not fully capture the full spectrum and complexity of disease expression. Many patients do not harbor identifiable pathogenic variants, while others carrying well-known disease-causing variants remain unaffected. This highlights the role of incomplete penetrance, likely modulated by additional genetic modifiers. Recent advances in genomics have revealed a broader view of the genetic basis of cardiomyopathies, introducing new players such as common genetic variants identified as risk alleles, as well as intermediate-effect variants. This continuum of genetic risk, reflecting an overall genetic influence, interacts further with environmental and lifestyle factors, likely contributing together to the observed variability in clinical presentation. This model offers a more realistic framework for understanding genetic inheritance and helps provide a clearer picture of disease expression and penetrance. This review explores the evolving genetic architecture of cardiomyopathies, spanning from a monogenic foundation to intermediate-risk variants and complex polygenic contribution. Recognizing this continuum is essential for enhancing diagnostic accuracy, guiding family screening strategies, and enabling personalized patient management. Full article

Predominantly antibody deficiencies (PADs) are the most prevalent types of inherited errors of immunity (IEI) and are characterized by a broad range of clinical manifestations, such as recurrent infections, autoimmunity, lymphoproliferation, atopy and malignancy. The aim of this study was to identify genetic defects associated with PADs in order to improve diagnosis and personalized care. Twenty patients (male/female: 12/8, median age of disease onset: 16.5 years, range: 1–50) were analyzed by next-generation sequencing (NGS) using a custom panel of 30 genes associated with PADs and their possible disease phenotype. The detected variants were classified according to the American College of Medical Genetics and Genomics (ACMG) guidelines and inheritance, and the penetrance patterns were evaluated by PCR–Sanger sequencing. Novel and rare mutations associated with the phenotype of common variable immunodeficiency (CVID) in genes encoding the transcription factors NFKB1, NFKB2 and IKZF1/IKAROS were identified. Alphafold3 protein structure prediction was utilized to perform a comprehensive visualization strategy and further delineate the mutation-bearing domains and elucidate their potential impact on protein function. This study highlights the value of genetic testing in PADs and will guide further research and improvement in diagnosis and treatment. Full article

This study aimed to investigate population genetic differences related to reproductive traits between Duroc and Yorkshire (Dutch Large White) pigs using two approaches: linear mixed models that dissect additive and dominant effects, and selective sweep analysis. (1) Methods: Genome-wide single-nucleotide polymorphism (SNP) data of 3917 Duroc and 3217 Yorkshire pigs were analyzed. The first principal component (PC1) was used as a simulated phenotype to capture population-level variance. Additive and dominant genetic effects were partitioned and evaluated by using the combination of the linear mixed models (LMM) and ADDO’s algorithm (LMM + ADDO). In parallel, selective sweep signals were detected using fixation index (F_ST) and nucleotide diversity (θ_π) analyses. A comparative assessment was then conducted between the LMM + ADDO and the selective sweep analysis results. Significant loci were annotated using quantitative trait loci (QTL) databases and the Ensembl genome browser. (2) Results: There are 39040 SNPs retained after quality control. Using the LMM + ADDO framework with PC1 as a simulated phenotype, a total of 632 significant SNPs and 184 candidate genes were identified. Notably, 587 SNPs and 171 genes were uniquely detected by the LMM + ADDO method and not among loci detected by the top 5% of F_ST and θ_π values. Key candidate genes associated with litter size included HSPG2, KAT6B, SAMD8, and LRMDA, while DLGAP1, MYOM1, and VTI1A were associated with teat number traits. (3) Conclusions: This study demonstrates the power of integrating additive and dominant effect modeling with population genetics approaches for the detection of genomic regions under selection. The findings provide novel insights into the genetic architecture of reproductive traits in pigs and have practical implications for understanding the inheritance of complex traits. Full article

To compare the clinical characteristics of inherited retinal diseases (IRDs) caused by biallelic versus monoallelic variants in the RP1, BEST1, and PROM1 genes. A total of 52 patients (26 female) with genetically confirmed IRDs were retrospectively selected from the records of the Harkness Eye Institute Clinical Coordinating Center at Columbia University Irving Medical Center. In RP1, 3 individuals with biallelic variants and 22 patients with monoallelic variants classified as pathogenic or likely pathogenic were selected. In BEST1, eight individuals with biallelic variants and nine individuals with monoallelic variants classified as either pathogenic or likely pathogenic were included. In PROM1, four individuals with biallelic variants and six patients with monoallelic variants classified as pathogenic or likely pathogenic were selected. All patients underwent multimodal retinal imaging and, when available, full-field electroretinography (ffERG). In all three genes, individuals with biallelic variants had markedly earlier disease onset and more severe phenotypes. In RP1, on SD-OCT, foveal involvement was observed in all biallelic cases (3/3, 100%) and in 4/22 (18%) monoallelic cases. In BEST1, the average age of onset in the biallelic cohort was 7.12 years, and the average age was 32.7 years in the monoallelic cohort. Four of eight (50%) patients in the biallelic group were additionally found to have widespread serous lesions outside of the central macula. This finding was not observed in the monoallelic group. Three of eight (38%) biallelic BEST1 patients had moderate reductions in their photopic flicker. All monoallelic BEST1 patients had photopic responses within the normal range. PROM1 biallelic cases showed severe functional impairment on ffERG, while most monoallelic cases retained normal responses. In the biallelic cohort, four of four (100%) of patients had severely attenuated or extinguished photopic responses. In the monoallelic PROM1 group, four of five (80%) monoallelic PROM1 patients had normal photopic responses, and P2-2 had mildly attenuated photopic responses. Individuals with biallelic variants exhibited earlier disease onset, more severe retinal degeneration, and significantly reduced retinal function compared with those with monoallelic variants. These observations highlight the role of loss-of-function mechanisms in more aggressive disease courses and underscore the importance of considering zygosity when determining prognosis and planning gene-based therapies. Full article

Objective: The clinical presentation of inherited retinal dystrophies associated with pathogenic variants in PRPH2 is highly variable. Here we present bilateral sector macular dystrophy as a novel clinical phenotype. Methods and analysis: Ophthalmologic examination, detailed retinal imaging with optical coherence tomography (OCT), OCT-angiography, fundus and near-infrared autofluorescence and molecular genetic testing were performed on a 30-year-old female. Results: The patient reported the onset of subjective visual disturbances 4.5 months prior to our first examination. Clinical examination and retinal imaging revealed bilateral sharply demarcated paracentral lesions in the temporal lower macula and otherwise normal retinal findings. Patient history revealed no medication or other possible causes for these unusual retinal lesions. Molecular genetic testing revealed a heterozygous c.623G>A variation (p.(Gly208Asp)) in the PRPH2 gene. Conclusions: Bilateral sectoral macular dystrophy has not been reported previously in any inherited retinal dystrophy. This feature adds to the wide spectrum of PRPH2-associated clinical presentations. Full article

Despite two extensive reprogramming events during early embryogenesis and gametogenesis, epigenetic information can be passed to the next generations, which constitutes the transgenerational epigenetic inheritance of phenotypes. Considering its utmost importance, there have been few studies focused on the transgenerational effects of dietary interventions, such as methionine supplementation, in livestock. Using whole-genome bisulfite sequencing, we implemented a single-base resolution differential methylation analysis for the F3 and F4 descendants of control vs. methionine-supplemented F0 twin-pair rams. Based on the results of our previous study on F0, F1, and F2 generations, we compared current results of 2981 and 1726 differentially methylated cytosines (DMCs), as well as 798 and 553 unique differentially methylated genes (DMGs), in F3 and F4, respectively. We identified 41 DMGs that exhibited transgenerational epigenetic inheritance (TEI-DMGs) across four generations and 11 TEI-DMGs across five generations. Finally, we estimated the effect size of F0 diet group on F3 and F4 growth and fertility-related phenotypes, providing evidence for transgenerational effects of diet group accompanying inherited differentially methylated genes. Here, for the first time using gene-level and phenotypic data, we demonstrate that a moderate dietary intervention can exert long-lasting transgenerational effects on offspring phenotypes extending beyond the F2 generation in sheep. Full article

The efficacy of in vitro fertilization (IVF) is significantly hindered by early embryonic developmental failure and oocyte maturation arrest. Recent findings in reproductive genetics have identified several oocyte-specific genes—TUBB8, KIF11, and CKAP5—as essential regulators of meiotic spindle formation and cytoskeletal dynamics. Mutations in these genes can lead to significant meiotic defects, fertilization failure, and embryo arrest. The links between genotype and phenotype, along with the underlying biological mechanisms, remain inadequately characterized despite the increasing number of identified variations. This systematic review was conducted in accordance with PRISMA 2020 guidelines. Relevant papers were retrieved from the PubMed and Embase databases using combinations of the keywords “TUBB8,” “KIF11,” “CKAP5,” “oocyte maturation arrest,” “embryonic arrest,” and “IVF failure.” Studies were included if they contained clinical, genomic, and functional data on TUBB8, KIF11, or CKAP5 mutations in women undergoing IVF. Molecular data, including gene variant classifications, inheritance models, in vitro tests (such as microtubule network analysis in HeLa cells), and assisted reproductive technology (ART) outcomes, were obtained. Eighteen trials including 35 women with primary infertility were included. Over fifty different variants were identified, the majority of which can be attributed to TUBB8 mutations. TUBB8 disrupted α/β-tubulin heterodimer assembly due to homozygous missense mutations, hence hindering meiotic spindle formation and leading to early embryo fragmentation or the creation of many pronuclei and cleavage failure. KIF11 mutations resulted in spindle disorganization and chromosomal misalignment via disrupting tubulin acetylation and microtubule transport. Mutations in CKAP5 impaired bipolar spindle assembly and microtubule stabilization. In vitro validation studies showed cytoskeletal disturbances, protein instability, and dominant negative effects in transfected animals. Donor egg IVF was the sole effective treatment; however, no viable pregnancies were documented in patients with pathogenic mutations of TUBB8 or KIF11. TUBB8, KIF11, and CKAP5 are essential for safeguarding oocyte meiotic competence and early embryonic development at the molecular level. Genetic differences in these genes disrupt microtubule dynamics and spindle assembly, resulting in various aspects of oocyte maturation and fertilization. Functional validation underscores the necessity of routine genetic screening for women experiencing unresolved IVF failure, as it substantiates their causal role in infertility. Future therapeutic avenues in ART may be enhanced by tailored counseling and innovative rescue methodologies like as gene therapy. Full article

The 26S proteasome is a large, ATP-dependent proteolytic complex responsible for degrading ubiquitinated proteins in eukaryotic cells. It plays a crucial role in maintaining cellular protein homeostasis by selectively eliminating misfolded, damaged, or regulatory proteins marked for degradation. In this study, whole-exome sequencing (WES) was performed on an individual presenting with developmental delay and mild intellectual disability, as well as on both of his unaffected parents. This analysis identified a de novo variant, c.959C>G (p.Pro320Arg), in the PSMC5 gene. As predicted, this gene shows a very likely autosomal dominant inheritance pattern. Notably, PSMC5 has not previously been associated with any phenotype in the OMIM database. This variant was recently submitted to the ClinVar database as a variant of uncertain significance (VUS) and remains absent in both gnomAD and dbSNP. Notably, it has been identified in six unrelated individuals presenting with clinical features comparable to those observed in the patient described in this study. Multiple in silico prediction tools classified the variant as pathogenic, and a PhyloP conservation score supports strong evolutionary conservation of the mutated nucleotide. Protein structure predictions using the AlphaFold3 algorithm revealed notable structural differences between the mutant and wild-type PSMC5 proteins. We hypothesize that the p.Pro320Arg substitution alters the structure and function of PSMC5 as a regulatory subunit of the 26S proteasome, potentially impairing the stability and activity of the entire complex. Although functional studies are imperative, this study contributes to a deeper understanding of PSMC5, expands the spectrum of associated neurodevelopmental phenotypes, and highlights its potential as a therapeutic target. Furthermore, this study resulted in the submission of the identified variant to the ClinVar database (SCV006083352), where it was classified as pathogenic. Full article