New research discovers psoriasis is linked with abnormalities in the copy number of mitochondrial DNA, suggesting its potential use as a novel blood-based biomarker.
A new study, published in PLOS ONE, investigated the correlation between mitochondrial DNA copy number (mtDNA-CN) and disease duration and severity of psoriasis.
Psoriasis is a chronic immune-mediated inflammatory skin disease, affecting approximately 2–3% of the worldwide population. It is associated with several comorbidities such as type 2 diabetes millets, cardiovascular disease, and hypertension. The appearance of comorbidities correlates with the severity of clinical presentation, typically increasing with age or disease duration.
At present, there is no specific or diagnostic blood test for psoriasis.
The study, conducted in the Department of Medical Laboratory in Kuwait University used real-time quantitative polymerase chain reaction (qPCR) to measure relative mtDNA-CN in 56 patients with the condition.
“Our study suggests that a low mtDNA-CN may serve as biomarker for early detection of psoriasis,” the authors reported.
Estimation of mtDNA-CN was determined by the ratio of mtDNA to nuclear DNA, which indicated the number of mitochondrial genomes per cell. With the use of real-time qPCR, the study found that psoriasis patients exhibited approximately a 50% reduction in mtDNA-CN.
The authors noted, “The low mtDNA-CN is a result of progressive impairment of oxidative phosphorylation and mitochondrial function, although this is a speculation that needs to be further investigated.”
Disease duration and severity
Having established a lower mtDNA-CN in patients, the researchers then evaluated the association of mtDNA-CN with disease duration and severity. Statistical analysis confirmed mtDNA-CN was significantly lower in patients with longer disease duration.
Results also showed that mtDNA-CN was significantly lower in patients with higher psoriasis area and severity index (PASI) scores, confirming a reduction in mtDNA-CN in more severe diagnoses.
The value of mtDNA-CN as a biomarker for psoriasis
The researchers then assessed the diagnostic value of mtDNA-CN using receiver operating characteristic (ROC) analysis. They found that mtDNA-CN can discriminate psoriasis patients from healthy controls at a 95% confidence interval.
Previous studies have revealed an essential role of mitochondrial defects in human aging and other pathological conditions, including psoriasis.
The authors reported, “mtDNA-CN is an especially attractive biomarker because it can be non-invasively measured in blood using a relatively easy and cheap method such as real-time PCR, in addition to the repeatability and reproducibility measurement of blood mtDNA-CN.”
The promising results and the cheap and reliable quantification of mtDNA-CN, highlight exciting potentials for utilising mtDNA-CN as a novel non-invasive biomarker for psoriasis.
Written by Harry Yuen, Science Writer Intern
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