The CC2D2A gene is essential for primary cilia formation, and its disruption has been associated with Joubert Syndrome-9 (JBTS9), a ciliopathy with typical neurodevelopmental features. Here, we describe an Italian pediatric patient with typical features of Joubert Syndrome (JBTS): “Molar Tooth Sign”, global developmental delay, nystagmus, mild hypotonia, and oculomotor apraxia. Whole exome sequencing and segregation analysis identified in our infant patient a novel heterozygous germline missense variant c.3626C > T; p.(Pro1209Leu) inherited from the father and a novel 7.16 kb deletion inherited from the mother. To the best of our knowledge, this is the first report showing a novel missense and deletion variant involving exon 30 of the CC2D2A gene.
Wilson’s disease (WD) is a rare autosomal recessive disorder caused by mutations in the ATP7B gene, resulting in copper accumulation. Symptoms rarely appear before the age of 5, almost never before 3. The phenotypic variability of WD suggests the presence of modifying factors, making early diagnosis challenging. We present a case of symptomatic WD in a toddler, emphasizing the importance of considering WD in differential diagnoses and exploring genetic modifiers influencing disease onset. Clinical and laboratory assessments, including liver biopsy, were performed on a 4.2‐year‐old boy presenting with hypertransaminasemia and mild hepatomegaly. Histological evaluation revealed chronic hepatitis with fibrosis and severe steatosis, indicating long‐standing active disease. Genetic analysis identified a missense variant and a 15‐nucleotide deletion in the 5′ UTR promoter region of the ATP7B gene, confirming the WD diagnosis. Additionally, homozygosity for the HFE H63D variant was detected, with transferrin saturations at the upper limit of normal. The patient’s clinical management included a trial of D‐penicillamine, discontinued due to side effects, followed by successful zinc acetate therapy. This case underscores the consideration of WD in the differential diagnosis of toddlers. The Ferenci‐Leipzig score remains a valid diagnostic tool for WD even in the presence of a single ATP7B variant, although extended genetic analysis should still be considered. Normal ceruloplasmin levels do not rule out WD. Environmental, epigenetic, and genetic factors appear to influence the WD phenotype; HFE variants may act as modifiers given the link between iron and copper homeostasis, possibly explaining the early symptomatic onset in our patient.
Background/Objectives: CLIFAHDD syndrome (OMIM # 616266) is a rare neurodevelopmental disorder caused by mutations in the NALCN gene. It is characterized by hypotonia, developmental delay, and congenital contractures of the limbs and face. We report a 33-year-old Italian woman with a mild form of CLIFAHDD who exhibited early-onset language difficulties and mild intellectual disability and later developed gait and balance impairments in adulthood. Methods and Results: Whole Exome Sequencing (WES) identified a novel missense variant c.1514A>T; p.(Lys505Met) in the NALCN gene. The allele frequency of this variant is not detected (MAF = 0.0), the variant is classified as likely pathogenic according to ACMG criteria, and predicted to be probably damaging by PolyPhen-2. It affects a critical residue within the second pore-forming domain of the NALCN channel, potentially altering lipid interactions and channel regulation. Sanger sequencing and segregation analysis confirmed the variant to be heterozygous and de novo. Conclusions: The patient’s milder symptoms and later onset, compared to severe pediatric cases, suggest that the clinical spectrum of CLIFAHDD syndrome may be broader than previously recognized. These findings underscore the potential influence of mutation location on disease presentation and severity.
Background/Objectives: Endplate lesions of the lumbar spine are often asymptomatic and frequently observed incidentally by radiological assessment. Variants in the vitamin D receptor gene (VDR) and an increase in some biochemical markers related to the osteo-cartilaginous metabolism were found in patients with endplate lesions. The aim of this study was to identify biochemical and genetic markers putatively associated with the presence of endplate lesions of the lumbar spine. Methods: Quantification of circulating bone remodeling proteins was obtained from 10 patients with endplate lesions and compared with age- and sex-matched controls. Whole exome sequencing (WES) was performed on patient genomic DNA using the Novaseq 6000 platform (Illumina, San Diego, CA, USA), obtaining a median read depth of 117×–200×, with ≥98% of regions covering at least 20×. The sequencing product was aligned to the reference genome (GRCh38.p13-hg38) and analyzed with Geneyx software. Results: We observed modifications in the levels of circulating proteins involved in bone remodeling and angiogenesis. We identified variants of interest in aggrecan (ACAN), bone morphogenetic protein 4 (BMP4), cytochrome P450 family 3 subfamily A member 4 (CYP3A4), GLI family zinc finger 2 (GLI2), heparan sulfate proteoglycan 2 (HSPG2), and mesoderm posterior bHLH transcription factor 2 (MESP2). VDR polymorphism (rs2228570) was present in nine patients, with the homozygotic ones having more severe endplate lesions and higher levels of the analyzed circulating markers in comparison with heterozygotic patients. Conclusions: These data represent interesting evidence of genetic variants, particularly in VDR, and altered levels of circulating markers of bone remodeling associated with endplate lesions, which should be confirmed in a larger population. The hypothesis suggested by our results is that the endplate lesions could be the consequence of an altered ossification mechanism at the vertebral level.