Rare pathogenic nucleotide variants of mitochondrial DNA associated with Leber’s hereditary optic neuropathy

Patients with Leber Hereditary Optic Neuropathy (LHON) in most cases have one of the three most common mutations: m.11778G>A in the ND4 gene, m.3460G>A in the ND1 gene, or m.14484T>C in the ND6 gene. According to the international Mitomap database, in addition to these three most common mutations, there are 16 other primary mutations that are even more rare. There are nucleotide substitutions that are classified as candidate or conditionally pathogenic mutations. Their involvement in the disease…

Gene therapy for mitochondrial disorders

In this review, we detail the current state of application of gene therapy to primary mitochondrial disorders (PMDs). Recombinant adeno-associated virus-based (rAAV) gene replacement approaches for nuclear gene disorders have been undertaken successfully in more than ten preclinical mouse models of PMDs which has been made possible by the development of novel rAAV technologies that achieve more efficient organ targeting. So far, however, the greatest progress has been made for Leber Hereditary…

The genetic puzzle of a SOD1-patient with ocular ptosis and a motor neuron disease: a case report

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with a complex genetic architecture, showing monogenic, oligogenic, and polygenic inheritance. In this study, we describe the case of a 71 years-old man diagnosed with ALS with atypical clinical features consisting in progressive ocular ptosis and sensorineural deafness. Genetic analyses revealed two heterozygous variants, in the SOD1 (OMIM*147450) and the TBK1 (OMIM*604834) genes respectively, and furthermore mitochondrial DNA…

DNAJC30 Gene Variants Are a Frequent Cause of a Rare Disease: Leber Hereditary Optic Neuropathy in Polish Patients

Leber hereditary optic neuropathy (LHON) is a rare disorder causing a sudden painless loss of visual acuity in one or both eyes, affecting young males in their second to third decade of life. The molecular background of the LHON is up to 90%, genetically defined by a point mutation in mitochondrial DNA. Recently, an autosomal recessive form of LHON (LHONAR1, arLHON) has been discovered, caused by biallelic variants in the DNAJC30 gene. This study provides the results of the DNAJC30 gene analysis…

Clinically Diagnosed Occult Macular Dystrophy Habouring an m.14502T>C Mitochondrial DNA Mutation Associated with Leber’s Hereditary Optic Neuropathy: Case Report and Literature Review

A 29-year-old female with no family history presented with bilateral progressive blurred vision. Her symptoms appeared at 12-years-old and her visual acuity had since deteriorated from 0.6 to 0.2 bilaterally with decreased critical flicker frequency and bilateral central scotomas. She did not have a relative afferent pupillary defect. Fundoscopy revealed no distinct disc hyperaemia, atrophy, or peripapillary telangiectatic vessels. The retinal nerve fibre layer appeared normal on optical…

Case report: Mutations in DNAJC30 causing autosomal recessive Leber hereditary optic neuropathy are common amongst Eastern European individuals

CONCLUSION: This finding adds to the growing cohort of patients with arLHON and demonstrates the importance of DNAJC30 screening in patients with molecularly undiagnosed LHON, particularly in Eastern European individuals. It is of heightened translational significance as patients diagnosed with arLHON exhibit a better prognosis and response to therapeutic treatment with the co-enzyme Q10 analog idebenone.