Heteroplasmy and phenotype spectrum of the mitochondrial tRNALeu (UUR) gene m.3243A&gt;G mutation in seven Han Chinese families

Liu, Gailing; Shen, Xiya; Sun, Ying; Lv, Qing; Li, Yuanyuan; Du, Ailian

doi:10.1016/j.jns.2019.116562

Cited by 15 publications

(9 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Higher heteroplasmy level, nervous system involvement, presentation of IPO are closely related to poor prognosis. 23 , 46 Recent 6 year follow up on 151 m.3243A>G mutation carriers showed that slowly progression of clinical score by 0.47 point increase of Newcastle Mitochondrial Disease Adult Scale (NMDAS) score per year. 47 Sun et al 48 analyzed 64 patients with MELAS syndrome and found that the medium survival time was 12 years.…”

Section: Disease Course and Prognosismentioning

confidence: 99%

The non-syndromic clinical spectrums of mtDNA 3243A>G mutation

Shen

2021

NSJ

Self Cite

View full text Add to dashboard Cite

The m.3243A >G mutation in the tRNA Leu )UUR( gene )MT-TL1( of the mitochondrial DNA is the most widely seen pathogenic mtDNA mutation which has major phenotypic variations. The clinical phenotype involves various organs such as the brain and nerves, skeletal muscles, heart, endocrine system, gastrointestinal tract, and skin. Some phenotypes conform to well established syndromes, while most of the symptoms appear individually or concomitant to other syndromes, making identification difficult. Furthermore, some progress has been made on cardiac manifestations as well as complications during pregnancy and perinatal period. This article provides a systematic review of the non-syndromic phenotypes and latest developments in m.3243A>G mutation.

show abstract

Section: Disease Course and Prognosismentioning

confidence: 99%

The non-syndromic clinical spectrums of mtDNA 3243A>G mutation

Shen

2021

NSJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…In contrast to this, the Spanish population did not show any haplogroup preference [40]. Concerning the geographical variations effect, we can notice that the native American haplogroup B2 was exhibited in Mexican MELAS females [101]; likewise, Eastern Asian haplogroups were detected in Chinese MELAS pedigrees [102] and in Indian MELAS patients [103].…”

Section: Discussionmentioning

confidence: 98%

Mutational Analysis and mtDNA Haplogroup Characterization in Three Serbian Cases of Mitochondrial Encephalomyopathies and Literature Review

et al. 2021

View full text Add to dashboard Cite

Mitochondrial encephalomyopathies (MEMP) are heterogeneous multisystem disorders frequently associated with mitochondrial DNA (mtDNA) mutations. Clinical presentation varies considerably in age of onset, course, and severity up to death in early childhood. In this study, we performed molecular genetic analysis for mtDNA pathogenic mutation detection in Serbian children, preliminary diagnosed clinically, biochemically and by brain imaging for mitochondrial encephalomyopathies disorders. Sanger sequencing analysis in three Serbian probands revealed two known pathogenic mutations. Two probands had a heteroplasmic point mutation m.3243A>G in the MT-TL1 gene, which confirmed mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episode syndrome (MELAS), while a single case clinically manifested for Leigh syndrome had an almost homoplasmic (close to 100%) m.8993T>G mutation in the MT-ATP6 gene. After full mtDNA MITOMASTER analysis and PhyloTree build 17, we report MELAS’ association with haplogroups U and H (U2e and H15 subclades); likewise, the mtDNA-associated Leigh syndrome proband shows a preference for haplogroup H (H34 subclade). Based on clinical–genetic correlation, we suggest that haplogroup H may contribute to the mitochondrial encephalomyopathies’ phenotypic variability of the patients in our study. We conclude that genetic studies for the distinctive mitochondrial encephalomyopathies should be well-considered for realizing clinical severity and possible outcomes.

show abstract

“…Among 13 patients with normal PTA, 10 patients with ABR could be elicited, two patients had a threshold shift up, and a single case of wave III latency was prolonged. There have been reports that OAE in MEM with SNHL was normal, but ABR was absent even after neurological symptoms and hearing loss occurred [ 34 ]. As for subjective testing, SDS and PTA results matched, and the SDS and PTA decreased disproportionately in only one case.…”

Section: Discussionmentioning

confidence: 99%

ENT characteristics and therapeutic results in multisystemic disorders of mitochondrial encephalomyopathy

et al. 2022

View full text Add to dashboard Cite

Here we report the evaluation of the frequency of subjective and objective otolaryngologic findings and therapeutic results in 32 patients with mitochondrial encephalomyopathy (MEM) from September 2001 to June 2021. Our analysis included studying the patients’ family histories, the clinical manifestations of MEM, and the therapeutic effects of treatments. The patients’ ages ranged from 2 to 77 years, with a median age of 12.3 years. We found that MEM ENT symptoms were characterized by hearing loss, dysphagia, and facial weakness. Most cases of sensorineural hearing loss were bilateral symmetrical progressive or sudden deafness since adolescence, which were often underestimated. Associated neuromuscular symptoms required mtDNA testing. Dysphagia and facial weakness occurred preferentially in middle-aged patients, and muscle biopsies were advised. Distortion product otoacoustic emissions and auditory brainstem responsetesting were more sensitive and reliable than pure tone averages for objective monitoring of pathogenesis. Administration of the mitochondrial synthase complex benefited patients with acute episodes. If patients did not fully recover and exhibitedresidual language deficits, hearing aids or cochlear implants were recommended. Counsel was given regarding synthetical treatments for facial weakness, endoscopic circopharyngealmyotomy for dysphagia, and surgical correction of ptosis. This study demonstrates that increased awareness of these symptoms is important to address appropriate interventions and avoid complications such as ablepsia, aphasia, social isolation, malnutrition, aspiration pneumonia, and heart failure in the setting of MEM.

show abstract

Heteroplasmy and phenotype spectrum of the mitochondrial tRNALeu (UUR) gene m.3243A>G mutation in seven Han Chinese families

Cited by 15 publications

References 34 publications

The non-syndromic clinical spectrums of mtDNA 3243A>G mutation

The non-syndromic clinical spectrums of mtDNA 3243A>G mutation

Mutational Analysis and mtDNA Haplogroup Characterization in Three Serbian Cases of Mitochondrial Encephalomyopathies and Literature Review

ENT characteristics and therapeutic results in multisystemic disorders of mitochondrial encephalomyopathy

Contact Info

Product

Resources

About