Variant Location Is a Novel Risk Factor for Individuals With Arrhythmogenic Cardiomyopathy Due to a Desmoplakin () Truncating Variant.

Background: Truncating variants in desmoplakin (tv) are an important cause of arrhythmogenic cardiomyopathy; however the genetic architecture and genotype-specific risk factors are incompletely understood. We evaluated phenotype, risk factors for ventricular arrhythmias, and underlying genetics of tv cardiomyopathy.

Methods: Individuals with tv and any cardiac phenotype, and their gene-positive family members were included from multiple international centers.

Harmonizing the Collection of Clinical Data on Genetic Testing Requisition Forms to Enhance Variant Interpretation in Hypertrophic Cardiomyopathy (HCM): A Study from the ClinGen Cardiomyopathy Variant Curation Expert Panel.

Diagnostic laboratories gather phenotypic data through requisition forms, but there is no consensus as to which data are essential for variant interpretation. The ClinGen Cardiomyopathy Variant Curation Expert Panel defined a phenotypic data set for hypertrophic cardiomyopathy (HCM) variant interpretation, with the goal of standardizing requisition forms. Phenotypic data elements listed on requisition forms from nine leading cardiomyopathy testing laboratories were compiled to assess divergence in data collection.

Neuronal ceroid lipofuscinosis type 2: an Australian case series.

Aim: Late infantile neuronal ceroid lipofuscinosis type 2 (CLN2) disease is a rare neurodegenerative disorder presenting in children aged 2-4 years with seizures and loss of motor and language skills, followed by blindness and death in late childhood. Initial presenting features are similar to a range of common epilepsies. We aim to highlight typical clinical and radiological features that may prompt diagnosis of CLN2 disease in early disease stages.

Study protocol of a multicentre cohort pilot study implementing an expanded preconception carrier-screening programme in metropolitan and regional Western Australia.

Introduction: Preconception carrier screening (PCS) identifies couples at risk of having children with recessive genetic conditions. New technologies have enabled affordable sequencing for multiple disorders simultaneously, including identifying carrier status for many recessive diseases. The aim of the study was to identify the most effective way of delivering PCS in Western Australia (WA) through the public health system.

β-Mannosidosis in German Shepherd Dogs.

A neurological disease was investigated in 3 German Shepherd pups from the same litter that failed to grow normally, appeared stiff, were reluctant to move, and were deaf. They developed intermittent seizures and ataxia and had proprioceptive defects. Histopathology showed severe vacuolation of neurons, astrocytes in nervous tissue, renal tubular epithelial cells, and macrophages in nervous tissue, spleen, and liver.

A case of vascular Ehlers-Danlos Syndrome with a cardiomyopathy and multi-system involvement.

Ehlers-Danlos Syndrome comprises a heterogeneous group of heritable connective tissue disorders resulting from various gene mutations. We present an unusual case of vascular Ehlers-Danlos Syndrome with distinctive physical characteristics and a cardiomyopathy with features suggesting isolated left ventricular non-compaction. The cardiac features represent the first report of a cardiomyopathy associated with a mutation in the COL3A1 gene.

Diagnosis of neuronal ceroid lipofuscinosis type 2 (CLN2 disease): Expert recommendations for early detection and laboratory diagnosis.

Neuronal ceroid lipofuscinoses (NCLs) are a heterogeneous group of lysosomal storage disorders. NCLs include the rare autosomal recessive neurodegenerative disorder neuronal ceroid lipofuscinosis type 2 (CLN2) disease, caused by mutations in the tripeptidyl peptidase 1 (TPP1)/CLN2 gene and the resulting TPP1 enzyme deficiency. CLN2 disease most commonly presents with seizures and/or ataxia in the late-infantile period (ages 2-4), often in combination with a history of language delay, followed by progressive childhood dementia, motor and visual deterioration, and early death.

Whole Exome Sequencing Reveals Compound Heterozygosity for Ethnically Distinct PEX7 Mutations Responsible for Rhizomelic Chondrodysplasia Punctata, Type 1.

We describe two brothers who presented at birth with bone growth abnormalities, followed by development of increasingly severe intellectual and physical disability, growth restriction, epilepsy, and cerebellar and brain stem atrophy, but normal ocular phenotypes. Case 1 died at 19 years of age due to chronic respiratory illnesses without a unifying diagnosis. The brother remains alive but severely disabled at 19 years of age.

Identifying the need for a multidisciplinary approach for early recognition of mucopolysaccharidosis VI (MPS VI).

Mucopolysaccharidosis VI (MPS VI, Maroteaux-Lamy syndrome) is caused by deficient activity of the enzyme, N-acetylgalactosamine-4-sulfatase, resulting in impaired degradation of the glycosaminoglycan dermatan sulfate. Patients experience a range of manifestations including joint contractures, short stature, dysostosis multiplex, coarse facial features, decreased pulmonary function, cardiac abnormalities, corneal clouding and shortened life span. Recently, clinicians from institutions in the Asia-Pacific region met to discuss the occurrence and implications of delayed diagnosis and misdiagnosis of MPS VI in the patients they have managed.

Overcoming the barriers to diagnosis of Morquio A syndrome.

Background: Morquio A syndrome is an autosomal recessive lysosomal storage disease often resulting in life-threatening complications. Early recognition and proficient diagnosis is imperative to facilitate prompt treatment and prevention of clinical complications.

Methods: Experts in Asia Pacific reviewed medical records focusing on presenting signs and symptoms leading to a diagnosis of Morquio A syndrome.

A systematic review of the prevalence of Morquio A syndrome: challenges for study reporting in rare diseases.

Background: Morquio A (MPS IVA) is a rare disease characterised by a deficiency of N-acetylgalactosamine-6 sulfatase (GALNS) and presenting with short stature, abnormal gait, cervical spine instability and shortened lifespan.

Purpose: To prepare a systematic review of the prevalence of Morquio A in multiple countries and suggest recommendations for reporting rare diseases.

Methods: Medline, Medline In-Process, Medline Daily Update, Embase, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, Health Technology Assessment Database and PROSPERO were searched from inception to October 2013 to identify relevant information on the epidemiology of Morquio A.

Klinefelter syndrome with fabry disease--a case of nondisjunction of the X-chromosome with sex-linked recessive mutation.

A 52 year-old male with Klinefelter syndrome presented with chest tightness and rapid atrial fibrillation with hypotension. His echocardiogram demonstrated symmetrical left ventricular hypertrophy with minimal diastolic dysfunction. Subsequent investigations confirmed the diagnosis of Fabry cardiomyopathy.

Ashkenazi Jewish population screening for Tay-Sachs disease: the international and Australian experience.

Internationally, Tay-Sachs disease (TSD) preconception screening of Ashkenazi Jewish (AJ) individuals and couples has led to effective primary prevention of TSD. In Australia, adolescent preconception genetic screening programs operate mainly in Jewish community high schools. These existing programs offer an effective means of primary prevention of TSD, are cost effective and safe.

Diagnosing mucopolysaccharidosis IVA.

Mucopolysaccharidosis IVA (MPS IVA; Morquio A syndrome) is an autosomal recessive lysosomal storage disorder resulting from a deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS) activity. Diagnosis can be challenging and requires agreement of clinical, radiographic, and laboratory findings. A group of biochemical genetics laboratory directors and clinicians involved in the diagnosis of MPS IVA, convened by BioMarin Pharmaceutical Inc.

Tay Sachs disease in Australia: reduced disease incidence despite stable carrier frequency in Australian Jews.

Objectives: To evaluate the outcomes of preconception screening of Jewish Australians for Tay Sachs disease (TSD) carrier status on Jewish TSD-affected births.

Design, Participants And Setting: Epidemiological observational study involving a complete retrospective audit of infantile and intermediate TSD cases diagnosed in Sydney and Melbourne between 1 January 1995 and 31 December 2011 (Royal Children's Hospital Melbourne; Pacific Laboratory Medicine Services, Pathology North, NSW Health Pathology, Sydney; Victorian Clinical Genetics Services, Melbourne; and SA Pathology, Adelaide), and carrier frequency among Jewish high school students attending schools participating in TSD screening programs over the same period.

Main Outcome Measures: Jewish TSD carrier frequency; and expected versus observed Jewish TSD-affected births.

Whole exome sequencing in foetal akinesia expands the genotype-phenotype spectrum of GBE1 glycogen storage disease mutations.

The clinically and genetically heterogenous foetal akinesias have low rates of genetic diagnosis. Exome sequencing of two siblings with phenotypic lethal multiple pterygium syndrome identified compound heterozygozity for a known splice site mutation (c.691+2T>C) and a novel missense mutation (c.

Hypertrophic cardiomyopathy with cardiac rupture and tamponade caused by congenital disorder of glycosylation type Ia.

Hypertrophic cardiomyopathy (HCM) is a rare presenting feature of congenital disorder of glycosylation type Ia (CDG-Ia). We report two female siblings with CDG-Ia and cardiomyopathy. Patient no.

Screening patients referred to a metabolic clinic for lysosomal storage disorders.

Background: Lysosomal protein profiling is being developed as a high throughput method to screen populations for lysosomal storage disorders (LSD).

Design: 1415 blood spots from patients referred to a metabolic clinic for LSD were screened using a single multiplex assay for 14 proteins in a dried blood spot.

Results: All patients with Pompe disease, metachromatic leukodystrophy, and mucopolysaccharidosis (MPS) type I, IIIA, IIIB and VI were identified by reduced lysosomal protein.

Refsum's Disease-Use of the Intestinal Lipase Inhibitor, Orlistat, as a Novel Therapeutic Approach to a Complex Disorder.

Refsum's Disease is an inherited metabolic disorder in which a metabolite of branched chain fatty acids accumulates due to lack of appropriate oxidative enzymes. Patients have elevated plasma phytanic acid levels and high concentrations of phytanic acid in a variety of tissues leading to progressive tissue damage. Besides retinal degeneration or retinal dystrophy associated with adult onset retinitis pigmentosa, additional symptoms include chronic polyneuropathy, cerebellar ataxia, sensorineural hearing loss, anosmia, ichthyosis, as well as skeletal, cardiac, hepatic, and renal abnormalities.

Identification of an unusual variant peroxisome biogenesis disorder caused by mutations in the PEX16 gene.

Background: Zellweger syndrome spectrum disorders are caused by mutations in any of at least 12 different PEX genes. This includes PEX16, which encodes an integral peroxisomal membrane protein involved in peroxisomal membrane assembly. PEX16-defective patients have been reported to have a severe clinical presentation.

The natural history and osteodystrophy of mucolipidosis types II and III.

Aim: To assess the natural history and impact of the secondary bone disease observed in patients with mucolipidosis (ML) II and III.

Methods: Affected children and adults were ascertained from clinical genetics units around Australia and New Zealand. Diagnoses were confirmed by the National Referral Laboratory in Adelaide.

Post-ictal psychosis in adolescent Niemann-Pick disease type C.

We describe the presentation of an adolescent with juvenile-onset Niemann-Pick disease type C (NPC) who presented with post-ictal psychosis in the context of a developing seizure disorder. After demonstrating mild gait disturbance beginning at the age of 4 years, he was diagnosed with NPC at age 12 on the basis of 95% of cultured fibroblasts staining positive for filipin and a reduced fibroblast cholesterol esterification rate. He then developed a seizure disorder at age 15, where clusters of seizures produced typical psychotic symptoms, including hallucinations and delusions.

Prenatal diagnosis of congenital disorder of glycosylation type Ia (CDG-Ia) by cordocentesis and transferrin isoelectric focussing of serum of a 27-week fetus with non-immune hydrops.

Blood was obtained by cordocentesis from a fetus with non-immune hydrops demonstrated by ultrasound scanning at 27 weeks' gestation. Abnormalities of serum transferrin isoelectric focussing (IEF) were identified, characteristic of a congenital disorder of glycosylation type I (CDG-Ia). A diagnosis of CDG-Ia was confirmed by enzyme analysis of cultured amniocytes.