We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
Technopath Clinical Diagnostics

Download Mobile App


ATTENTION: Due to the COVID-19 PANDEMIC, many events are being rescheduled for a later date, converted into virtual venues, or altogether cancelled. Please check with the event organizer or website prior to planning for any forthcoming event.

Precise Diagnosis of Mitochondrial Diseases Using Whole Genome Sequencing

By LabMedica International staff writers
Posted on 15 Nov 2021
Print article
Image: Very high magnification micrograph of a muscle biopsy specimen showing ragged red fibers, a finding seen in various types of mitochondrial diseases (Photo courtesy of Wikimedia Commons)
Image: Very high magnification micrograph of a muscle biopsy specimen showing ragged red fibers, a finding seen in various types of mitochondrial diseases (Photo courtesy of Wikimedia Commons)
A team of British researchers has demonstrated that a whole genome sequencing approach could identify patients with difficult to diagnose mitochondrial diseases and distinguish them from non-mitochondrial disorders.

Mitochondrial disorders are a common cause of inherited metabolic disease, affecting approximately 1 in 5000 people. They are caused by mutations in genes that primarily affect oxidative phosphorylation and ATP synthesis. Mitochondrial diseases take on unique characteristics both because of the way the diseases are often inherited and because mitochondria are so critical to cell function. Mitochondrial diseases are usually detected by analyzing muscle samples, where the presence of these organelles is higher. However, current genetic testing regimes fail to diagnose around 40% of patients, with major implications for patients.

In an effort to improve the diagnostics situation, investigators at the University of Cambridge (United Kingdom) and their colleagues at other institutions conducted a study to determine whether whole genome sequencing (WGS) could be used to define the molecular basis of suspected mitochondrial disorders.

For this study, the investigators performed short read whole genome sequencing on blood samples obtained from 345 patients with suspected mitochondrial disorders who were participants in the 100,000 Genomes Project in England between 2015 and 2018. The 100,000 Genomes Project was set up to embed genomic testing in the British National Health System, discover new disease genes, and make genetic diagnosis available for more patients.

Results obtained during the study revealed a definite or probable genetic diagnosis in 98/319 (31%) families, with an additional six (2%) possible diagnoses. Fourteen of the diagnoses (4% of the 319 families) explained only part of the clinical features. A total of 95 different genes were implicated. Of 104 families given a diagnosis, 39 (38%) had a mitochondrial diagnosis and 65 (63%) had a non-mitochondrial diagnosis.

The results showed that WGS was a useful diagnostic test in patients with suspected mitochondrial disorders, yielding a diagnosis in a further 31% after exclusion of common causes. Most diagnoses were non-mitochondrial disorders and included developmental disorders with intellectual disability, epileptic encephalopathies, other metabolic disorders, cardiomyopathies, and leukodystrophies. If a targeted approach had been taken, these diagnoses would have been missed.

Senior author Dr. Patrick Chinnery, professor of neurology at the University of Cambridge, said, “We recommend that whole genome sequencing should be offered early and before invasive tests such as a muscle biopsy. All that patients would need to do is have a blood test, meaning that this could be offered across the whole country in an equitable way. People would not need to travel long distances to multiple appointments, and they would get their diagnosis much faster.”

Considering that the majority of diagnoses were of non-mitochondrial disorders, Dr. Chinnery said, “These patients were referred because of a suspected mitochondrial disease and the conventional diagnostic tests are specifically for mitochondrial diseases. Unless you consider these other possibilities, you will not diagnose them. Whole genome sequencing is not restricted by that bias.”

The study was published in the November 4, 2021, online edition of the journal BMJ.

Related Links:
University of Cambridge

Gold Supplier
Multifuge X4 Pro Centrifuge Series
Vented Safety Enclosures
VSE Balance Enclosures
Cardiovascular Disease POC Analyzer
cobas h 232 POC System
Pancreatic Elastase ELISA Kit
Pancreatic Elastase ELISA

Print article



view channel
Image: The Gazelle Hb Variant Test for screening, diagnosis and management of sickle cell disease and related hemoglobinopathies at the point of care (Photo courtesy of Hemex Health)

Point-of-Care Device Accurately Rapidly Diagnoses Sickle Cell Disease

Hemoglobinopathies are the most common autosomal hereditary disorders. Approximately 7% of the global population carries hemoglobin gene mutation including structural hemoglobin variants like sickle hemoglobin... Read more


view channel
Image: The IMMULITE 2000 XPi Immunoassay System provides multiple tests on a single, easy-to-use analyzer, including the thyroid-stimulating immunoglobulin assay (Photo courtesy of Siemens Healthcare)

Immunoassays Evaluated for Thyroid-Stimulating Receptor Antibody in Graves’ Disease

Graves' disease (GD), also known as toxic diffuse goiter, is an autoimmune disease that affects the thyroid. It frequently results in and is the most common cause of hyperthyroidism and it also often results... Read more


view channel
Image: The sciREADER CL2 enables high quality digital colorimetric imaging of various support formats (Photo courtesy of SCIENION)

Multiplex Immunoassay Developed for Confirmation and Typing of HTLV Infections

Human T-Cell Lymphotropic Viruses (HTLV) type 1 and type 2 account for an estimated five to 10 million infections worldwide and are transmitted through breast feeding, sexual contacts and contaminated... Read more


view channel

AI Accurately Detects and Diagnoses Colorectal Cancer from Tissue Scans As Well or Better Than Pathologists

Artificial intelligence (A) can accurately detect and diagnose colorectal cancer from tissue scans as well or better than pathologists, according to a new study. The study, which was conducted by researchers... Read more


view channel
Image: PKeye Workflow Monitor System (Photo courtesy of PerkinElmer, Inc.)

PerkinElmer’s New Cloud-Based Platform Enables Laboratory Personnel to Remotely Manage Its Instruments in Real-Time

PerkinElmer, Inc. (Waltham, MA; USA) has launched its PKeye Workflow Monitor, a cloud-based platform enabling laboratory personnel to remotely manage and monitor their PerkinElmer instruments and workflows... Read more


view channel

Global Point of Care Diagnostics Market to Top USD 35 Billion by 2027 Due to Rising Diabetic Cases

The global point of care diagnostics market is projected to grow at a CAGR of close to 6% from more than USD 23 billion in 2020 to over USD 35 billion by 2027, driven by an increase in the number of diabetic... Read more
Copyright © 2000-2021 Globetech Media. All rights reserved.