Two novel variants in GRN: the relevance of CNV analysis and genetic screening in FTLD patients with a negative family history.

Background: Frontotemporal lobar degeneration (FTLD) is one of the leading causes of early onset dementia. Pathogenic variants in GRN have been reported to cause 5-25% of familial and 5% of sporadic FTLD. Here, we present two novel, likely pathogenic variants in GRN.

Clinical, neuroimaging and genetic findings in Brazilian patients with neurodegeneration with brain iron accumulation.

Neurodegeneration with brain iron accumulation (NBIA) encompasses a clinically and genetically heterogeneous group of rare disorders. Here, we report clinical, neuroimaging and genetic studies in twenty three Brazilian NBIA patients. In thirteen subjects, deleterious variants were detected in known NBIA-causing genes (PANK2, PLA2G6, C9ORF12, WDR45 and FA2H), including previously unreported variants in PANK2 and PLA2G6.

LRP10 and α-synuclein transmission in Lewy body diseases.

Autosomal dominant variants in LRP10 have been identified in patients with Lewy body diseases (LBDs), including Parkinson's disease (PD), Parkinson's disease-dementia (PDD), and dementia with Lewy bodies (DLB). Nevertheless, there is little mechanistic insight into the role of LRP10 in disease pathogenesis. In the brains of control individuals, LRP10 is typically expressed in non-neuronal cells like astrocytes and neurovasculature, but in idiopathic and genetic cases of PD, PDD, and DLB, it is also present in α-synuclein-positive neuronal Lewy bodies.

deCLUTTER2+ - a pipeline to analyze calcium traces in a stem cell model for ventral midbrain patterned astrocytes.

Astrocytes are the most populous cell type of the human central nervous system and are essential for physiological brain function. Increasing evidence suggests multiple roles for astrocytes in Parkinson's disease, nudging a shift in the research focus, which historically pivoted around ventral midbrain dopaminergic neurons (vmDANs). Studying human astrocytes and other cell types in vivo remains challenging.

PTPA variants and impaired PP2A activity in early-onset parkinsonism with intellectual disability.

The protein phosphatase 2A complex (PP2A), the major Ser/Thr phosphatase in the brain, is involved in a number of signalling pathways and functions, including the regulation of crucial proteins for neurodegeneration, such as alpha-synuclein, tau and LRRK2. Here, we report the identification of variants in the PTPA/PPP2R4 gene, encoding a major PP2A activator, in two families with early-onset parkinsonism and intellectual disability. We carried out clinical studies and genetic analyses, including genome-wide linkage analysis, whole-exome sequencing, and Sanger sequencing of candidate variants.

A new alpha-synuclein missense variant (Thr72Met) in two Turkish families with Parkinson's disease.

Introduction: Missense variants and multiplications of the alpha-synuclein gene (SNCA) are established as rare causes of autosomal dominant forms of Parkinson's Disease (PD).

Methods: Two families of Turkish origins with PD were studied; the SNCA coding region was analyzed by Sanger sequencing, and by whole exome sequencing (WES) in the index patient of the first and the second family, respectively. Co-segregation studies and haplotype analysis across the SNCA locus were carried out.

LRP10 interacts with SORL1 in the intracellular vesicle trafficking pathway in non-neuronal brain cells and localises to Lewy bodies in Parkinson's disease and dementia with Lewy bodies.

Loss-of-function variants in the low-density lipoprotein receptor-related protein 10 (LRP10) gene have been associated with autosomal-dominant Parkinson's disease (PD), PD dementia, and dementia with Lewy bodies (DLB). Moreover, LRP10 variants have been found in individuals diagnosed with progressive supranuclear palsy and amyotrophic lateral sclerosis. Despite this genetic evidence, little is known about the expression and function of LRP10 protein in the human brain under physiological or pathological conditions.

EIF2AK2 Missense Variants Associated with Early Onset Generalized Dystonia.

Objective: The study was undertaken to identify a monogenic cause of early onset, generalized dystonia.

Methods: Methods consisted of genome-wide linkage analysis, exome and Sanger sequencing, clinical neurological examination, brain magnetic resonance imaging, and protein expression studies in skin fibroblasts from patients.

Results: We identified a heterozygous variant, c.

Late-onset phenotype associated with a homozygous GJC2 missense mutation in a Turkish family.

Objective: Recessive mutations in the Gap Junction Protein Gamma 2 (GJC2) gene cause Pelizaeus-Merzbacher-like disease type 1, a severe infantile-onset hypomyelinating leukodystrophy. Milder, late-onset phenotypes including complicated spastic paraplegia in one family (SPG44), and mild tremor in one case, were reported associated to GJC2 homozygous missense mutations. Here, we report a new family with two siblings carrying a different homozygous GJC2 mutation, presenting with late-onset ataxic and pyramidal disturbances, and parkinsonism in one of them.

Low prevalence of known pathogenic mutations in dominant PD genes: A Swedish multicenter study.

Objective: To determine the frequency of mutations known to cause autosomal dominant Parkinson disease (PD) in a series with more than 10% of Sweden's estimated number of PD patients.

Methods: The Swedish Parkinson Disease Genetics Network was formed as a national multicenter consortium of clinical researchers who together have access to DNA from a total of 2,206 PD patients; 85.4% were from population-based studies.

LRP10 variants in Parkinson's disease and dementia with Lewy bodies in the South-West of the Netherlands.

Objective: To analyse LRP10 variants, recently associated with the development of Parkinson's disease (PD), Parkinson's disease dementia (PDD) and dementia with Lewy bodies (DLB), in a series of patients and controls from the South-West of the Netherlands (Walcheren).

Methods: A series of 130 patients with PD, PDD or DLB were clinically examined, and a structured questionnaire used to collect information about family history of PD and dementia. The entire LRP10 coding region was sequenced by Sanger methods in all patients, and haplotype analysis was performed for one recurrent LRP10 variant.

PTRHD1 Loss-of-function mutation in an african family with juvenile-onset Parkinsonism and intellectual disability.

Background: The genetic bases of PD in sub-Saharan African (SSA) populations remain poorly characterized, and analysis of SSA families with PD might lead to the discovery of novel disease-related genes.

Objectives: To investigate the clinical features and identify the disease-causing gene in a black South African family with 3 members affected by juvenile-onset parkinsonism and intellectual disability.

Methods: Clinical evaluation, neuroimaging studies, whole-exome sequencing, homozygosity mapping, two-point linkage analysis, and Sanger sequencing of candidate variants.

LRP10 genetic variants in familial Parkinson's disease and dementia with Lewy bodies: a genome-wide linkage and sequencing study.

Background: Most patients with Parkinson's disease, Parkinson's disease dementia, and dementia with Lewy bodies do not carry mutations in known disease-causing genes. The aim of this study was to identify a novel gene implicated in the development of these disorders.

Methods: Our study was done in three stages.

homozygous missense mutation associated with complicated hereditary spastic paraplegia.

Objective: To identify the clinical characteristics and genetic etiology of a family affected with hereditary spastic paraplegia (HSP).

Methods: Clinical, genetic, and functional analyses involving genome-wide linkage coupled to whole-exome sequencing in a consanguineous family with complicated HSP.

Results: A homozygous missense mutation was identified in the gene (c.

Candidate CSPG4 mutations and induced pluripotent stem cell modeling implicate oligodendrocyte progenitor cell dysfunction in familial schizophrenia.

Schizophrenia is highly heritable, yet its underlying pathophysiology remains largely unknown. Among the most well-replicated findings in neurobiological studies of schizophrenia are deficits in myelination and white matter integrity; however, direct etiological genetic and cellular evidence has thus far been lacking. Here, we implement a family-based approach for genetic discovery in schizophrenia combined with functional analysis using induced pluripotent stem cells (iPSCs).

The p.Thr11Met mutation in c19orf12 is frequent among adult Turkish patients with MPAN.

Introduction: Mutations in the C19orf12 gene cause mitochondrial membrane protein associated neurodegeneration (MPAN), an autosomal recessive form of neurodegeneration with brain iron accumulation (NBIA). A limited number of patients with C19orf12 mutations, particularly those with adult onset of symptoms, have been reported.

Methods: We sequenced the entire coding region of C19orf12 in 15 Turkish adult probands with idiopathic NBIA.

A balanced translocation disrupting BCL2L10 and PNLDC1 segregates with affective psychosis.

Affective psychoses are a group of severe psychiatric disorders, including schizoaffective disorder and bipolar I disorder, together affecting ∼1% of the population. Despite their high heritability, the molecular genetics and neurobiology of affective psychosis remain largely elusive. Here, we describe the identification of a structural genetic variant segregating with affective psychosis in a family with multiple members suffering from bipolar I disorder or schizoaffective disorder, bipolar type.