An evidence-based practice guideline of the National Society of Genetic Counselors for telehealth genetic counseling.

There are currently no practice guidelines available for genetic counseling using telehealth modalities. This evidence-based practice guideline was developed in response to increasing use of alternative service delivery models for genetic counseling, specifically telephone and video-based genetic counseling (telehealth genetic counseling or THGC). A recent systematic evidence review (SER) compared outcomes of THGC with in-person genetic counseling and found that for the majority of studied outcomes, THGC was a non-inferior and comparable service delivery model.

Genetic testing and diagnosis of inherited retinal diseases.

Inherited retinal diseases (IRDs) are a diverse group of degenerative diseases of the retina that can lead to significant reduction in vision and blindness. Because of the considerable phenotypic overlap among IRDs, genetic testing is a critical step in obtaining a definitive diagnosis for affected individuals and enabling access to emerging gene therapy-based treatments and ongoing clinical studies. While advances in molecular diagnostic technologies have significantly improved the understanding of IRDs and identification of disease-causing variants, training in genetic diagnostics among ophthalmologists is limited.

The current status of molecular diagnosis of inherited retinal dystrophies.

Purpose Of Review: We are witnessing lightning-fast advances in the molecular diagnosis of inherited retinal dystrophies, mainly due to the widespread use of next-generation sequencing technologies. The purpose of this review is to highlight the breadth of findings from this in-depth testing approach, and to propose changes to our traditional testing and diagnostic paradigms. Lessons learned from modern molecular testing suggest that the previous concept of inherited retinal dystrophies as a group of 'single gene diseases' may require a significant update.

Mutations in RPGR and RP2 account for 15% of males with simplex retinal degenerative disease.

Purpose: To determine the proportion of male patients presenting simplex retinal degenerative disease (RD: retinitis pigmentosa [RP] or cone/cone-rod dystrophy [COD/CORD]) with mutations in the X-linked retinal degeneration genes RPGR and RP2.

Methods: Simplex males were defined as patients with no known affected family members. Patients were excluded if they had a family history of parental consanguinity.

The phenotype of Severe Early Childhood Onset Retinal Dystrophy (SECORD) from mutation of RPE65 and differentiation from Leber congenital amaurosis.

Purpose: To describe in detail the characteristic clinical phenotype and electrophysiological features of Severe Early Childhood Onset Retinal Dystrophy (SECORD) caused by mutation of RPE65.

Methods: Ophthalmological examination, color fundus photography, visual field testing, detailed electrophysiological assessment, and screening of RPE65 were undertaken in five subjects. Selected patients also had spectral domain optical coherence tomography.

Frequency of Usher syndrome in two pediatric populations: Implications for genetic screening of deaf and hard of hearing children.

Purpose: Usher syndrome is a major cause of genetic deafness and blindness. The hearing loss is usually congenital and the retinitis pigmentosa is progressive and first noticed in early childhood to the middle teenage years. Its frequency may be underestimated.

Combined retinal hamartomas leading to the diagnosis of neurofibromatosis type 2.

Purpose: To report two cases of neurofibromatosis type 2 (NF2) initially presenting with isolated bilateral combined hamartomas of the retina and retinal pigment epithelium (RPE).

Methods: Retrospective observational case reports.

Results: Two unrelated children presented to ophthalmology with isolated combined hamartomas of the retina and RPE.

Choroideremia: analysis of the retina from a female symptomatic carrier.

Purpose: To define the retinal pathology in a 91 year-old affected matriarch of a three-generation choroideremia family with multiple manifesting carriers.

Methods: Tissue from three different retinal areas was processed for immunohistochemistry. The macular area was processed for transmission electron microscopy.

Novel mutations in the KCNV2 gene in patients with cone dystrophy and a supernormal rod electroretinogram.

Purpose: To identify mutations in KCNV2 in patients with a form of cone dystrophy characterized by a supernormal rod electroretinogram (ERG).

Methods: The 2 exons and flanking intron DNA of KCNV2 from 8 unrelated patients were PCR amplified and sequenced.

Results: We found 1 frameshift, 2 nonsense, 1 non-stop, and 6 missense mutations.

Microcephaly with chorioretinopathy in a brother-sister pair: evidence for germ line mosaicism and further delineation of the ocular phenotype.

Microcephaly with chorioretinopathy (OMIM 156590) is an autosomal dominant syndrome, characterized primarily by chorioretinal lesions and microcephaly. The phenotype is variable, and has been described in association with retinal dysplasia that can be stable or show progressive degeneration, retinal folds, lymphedema, and mental retardation. We describe two siblings with microcephaly, mental retardation, and variable retinal and choroidal abnormalities.

Molecular testing for hereditary retinal disease as part of clinical care.

Objective: To describe clinical molecular testing for hereditary retinal degenerations, highlighting results, interpretation, and patient education.

Methods: Mutation analysis of 8 retinal genes was performed by dideoxy sequencing. Pretest and posttest genetic counseling was offered to patients.

Clinical and electrophysiologic characterization of paraneoplastic and autoimmune retinopathies associated with antienolase antibodies.

Purpose: Paraneoplastic and autoimmune retinopathies are immunologically mediated retinal degenerations that are associated with antibodies directed against any of several retinal proteins, including alpha-enolase. We report the clinical and electrophysiological features of antienolase retinopathy in contrast to the features of antirecoverin retinopathy.

Design: Retrospective, observational case series.

Electroretinographic and clinicopathologic correlations of retinal dysfunction in infantile neuronal ceroid lipofuscinosis (infantile Batten disease).

Infantile neuronal ceroid lipofuscinosis (INCL) is an autosomal recessive disease that results from deficiency of palmitoyl-protein thioesterase-1 (PPT1). INCL leads to retinal blindness, neurodegeneration, and early death. We studied the clinical features and electroretinogram (ERG) in three patients and histopathologic and immunofluorescence analyses of the retina in the third patient, who died at 3 years 2 months of age.

Treatment of retinal and choroidal degenerations and dystrophies: current status and prospects for gene-based therapy.

Inherited retinal and choroidal degenerations account for a significant portion of blindness in children and young adults. This article reviews the current status and future prospects for the treatment of these disorders. Current treatment strategies include nutritional intervention for gyrate atrophy of the choroid and retina with hyperornithinemia, abetalipoproteinemia, and Refsum's disease, as well as vitamin A supplementation for retinitis pigmentosa.