11 research outputs found
ALPK1 missense pathogenic variant in five families leads to ROSAH syndrome, an ocular multisystem autosomal dominant disorder
Purpose: To identify the molecular cause in five unrelated families
with a distinct autosomal dominant ocular systemic disorder we
called ROSAH syndrome due to clinical features of retinal dystrophy,
optic nerve edema, splenomegaly, anhidrosis, and migraine headache.
Methods: Independent discovery exome and genome sequencing
in families 1, 2, and 3, and confirmation in families 4 and 5.
Expression of wild-type messenger RNA and protein in human and
mouse tissues and cell lines. Ciliary assays in fibroblasts from
affected and unaffected family members.
Results: We found the heterozygous missense variant in the Ékinase gene, ALPK1, (c.710C>T, [p.Thr237Met]), segregated with
disease in all five families. All patients shared the ROSAH
phenotype with additional low-grade ocular inflammation, pancytopenia, recurrent infections, and mild renal impairment in some.
ALPK1 was notably expressed in retina, retinal pigment epithelium,
and optic nerve, with immunofluorescence indicating localization
to the basal body of the connecting cilium of the photoreceptors,
and presence in the sweat glands. Immunocytofluorescence
revealed expression at the centrioles and spindle poles during
metaphase, and at the base of the primary cilium. Affected family
member fibroblasts demonstrated defective ciliogenesis.
Conclusion: Heterozygosity for ALPK1, p.Thr237Met leads to
ROSAH syndrome, an autosomal dominant ocular systemic
disorder
Genotyping of Toxoplasma gondii by Multiplex PCR and Peptide-Based Serological Testing of Samples from Infants in Poland Diagnosed with Congenital Toxoplasmosis
Toxoplasma gondii has a clonal population genetic structure with three (I, II, and III) lineages that predominate in North America and Europe. Type II strains cause most cases of symptomatic human infections in France and the United States, although few other regions have been adequately sampled. Here we determined the parasite genotype in amniotic fluid and cerebrospinal fluid samples from congenital toxoplasmosis cases in Poland. Nineteen confirmed congenital cases of toxoplasmosis were analyzed, including both severe and asymptomatic cases. The genotype of parasite strains causing congenital infection was determined by direct PCR amplification and restriction fragment length polymorphism analysis. Nested multiplex PCR analysis was used to type four independent polymorphic markers. The sensitivity of multiplex nested PCR was â„25 parasites/ml in amniotic fluid and cerebral spinal fluid samples. Parasite DNA was successfully amplified in 9 of 19 samples (eight severely affected and one asymptomatic fetus). Only genotype II parasites were identified as the source of T. gondii infection based on restriction fragment length polymorphism analysis. Strains causing congenital infections were also typed indirectly based on detection of antibodies to strain-specific peptides. Serotyping indicated that 12 of 15 cases tested were caused by type II strains and these positives included both symptomatic and asymptomatic infections. Overall, the combined analysis indicated that 14 of the cases were caused by type II strains. Our results are consistent with the hypothesis that parasite burden is associated with severity of congenital toxoplasmosis and indicate that serological testing provides a promising method for genotypic analysis of toxoplasmosis
Discovery of autism/intellectual disability somatic mutations in Alzheimer's brains : mutated ADNP cytoskeletal impairments and repair as a case study
With Alzheimerâs disease (AD) exhibiting reduced ability of neural stem cell renewal, we hypothesized that de novo mutations controlling embryonic development, in the form of brain somatic mutations instigate the disease. A leading gene presenting heterozygous dominant de novo autism-intellectual disabilities (ID) causing mutations is activity-dependent neuroprotective protein (ADNP), with intact ADNP protecting against AD-tauopathy. We discovered a genomic autism ADNP mutation (c.2188C>T) in postmortem AD olfactory bulbs and hippocampi. RNA-Seq of olfactory bulbs also identified a novel ADNP hotspot mutation, c.2187_2188insA. Altogether, 665 mutations in 596 genes with 441 mutations in AD patients (389 genes, 38% ADâexclusive mutations) and 104 genes presenting disease-causing mutations (OMIM) were discovered. OMIM AD mutated genes converged on cytoskeletal mechanisms, autism and ID causing mutations (about 40% each). The number and average frequencies of AD-related mutations per subject were higher in AD subjects compared to controls. RNA-seq datamining (hippocampus, dorsolateral prefrontal cortex, fusiform gyrus and superior frontal gyrusâ583 subjects) yielded similar results. Overlapping all tested brain areas identified unique and shared mutations, with ADNP singled out as a gene associated with autism/ID/AD and presenting several unique aging/AD mutations. The large fusiform gyrus library (117 subjects) with high sequencing coverage correlated the c.2187_2188insA ADNP mutation frequency to Braak stage (tauopathy) and showed more ADNP mutations in AD specimens. In cell cultures, the ADNP-derived snippet NAP inhibited mutated-ADNP-microtubule (MT) toxicity and enhanced TauâMT association. We propose a paradigm-shifting concept in the perception of AD whereby accumulating mosaic somatic mutations promote brain pathology