Widening the infantile hypotonia with psychomotor retardation and characteristic Facies-1 Syndrome's clinical and molecular spectrum through NALCN structural analysis.

Introduction: Infantile hypotonia with psychomotor retardation and characteristic facies-1 (IHPRF1, MIM#615419) is a rare, birth onset, autosomal recessive disorder caused by homozygous or compound heterozygous truncating variants in gene (MIM#611549) resulting in a loss-of-function effect.

Methods: We enrolled a new IHPRF1 patients' cohort in the framework of an international multicentric collaboration study. Using specialized pathogenicity predictors and structural analyses, we assessed the mechanistic consequences of the deleterious variants retrieved on NALCN structure and function.

Molecular and clinical Insights into KMT2E-Related O'Donnell-Luria-Rodan syndrome in a novel patient cohort.

O'Donnell-Luria-Rodan (ODLURO) syndrome is an autosomal dominant neurodevelopmental disorder mainly characterized by global development delay/intellectual disability, white matter abnormalities, and behavioral manifestations. It is caused by pathogenic variants in the KMT2E gene. Here we report seven new patients with loss-of-function KMT2E variants, six harboring frameshift/nonsense changes, and one with a 7q22.

Exploiting structural analysis to introduce emerging genotype-phenotype correlations in DHCR24-related sterol biosynthesis disorder: a case study.

Desmosterolosis is a rare sterol biosynthesis disorder characterized by multiple congenital anomalies, failure to thrive, severe developmental delay, progressive epileptic encephalopathy, and elevated levels of desmosterol caused by biallelic mutations of encoding 3-β-hydroxysterol Δ-24-reductase. DHCR24 is regarded as the key enzyme of cholesterol synthesis in the metabolism of brain cholesterol as it catalyzes the reduction of the Δ-24 double bond of sterol intermediates during cholesterol biosynthesis. To date, 15 variants, detected in 2 related and 14 unrelated patients, have been associated with the desmosterolosis disorder.