Genetic variants affecting NQO1 protein levels impact the efficacy of idebenone treatment in Leber hereditary optic neuropathy.

Idebenone, the only approved treatment for Leber hereditary optic neuropathy (LHON), promotes recovery of visual function in up to 50% of patients, but we can neither predict nor understand the non-responders. Idebenone is reduced by the cytosolic NAD(P)H oxidoreductase I (NQO1) and directly shuttles electrons to respiratory complex III, bypassing complex I affected in LHON. We show here that two polymorphic variants drastically reduce NQO1 protein levels when homozygous or compound heterozygous. This hampers idebenone reduction. In its oxidized form, idebenone inhibits complex I, decreasing respiratory function in cells. By retrospectively analyzing a large cohort of idebenone-treated LHON patients, classified by their response to therapy, we show that patients with homozygous or compound heterozygous NQO1 variants have the poorest therapy response, particularly if carrying the m.3460G>A/MT-ND1 LHON mutation. These results suggest consideration of patient NQO1 genotype and mitochondrial DNA mutation in the context of idebenone therapy.

RNA sequencing role and application in clinical diagnostic.

Although whole-exome sequencing and whole-genome sequencing has tremendously improved our understanding of the genetic etiology of human disorders, about half of the patients still do not receive a molecular diagnosis. The high fraction of variants with uncertain significance and the challenges of interpretation of noncoding variants have urged scientists to implement RNA sequencing (RNA-seq) in the diagnostic approach as a high throughput assay to complement genomic data with functional evidence. RNA-seq data can be used to identify aberrantly spliced genes, detect allele-specific expression, and identify gene expression outliers. Amongst eight studies utilizing RNA-seq, a mean diagnostic uplift of 15% has been reported. Here, we provide an overview of how RNA-seq has been implemented to aid in identifying the causal variants of Mendelian disorders.

Revisiting the AIDS Epidemic in Pakistan: Where We Stand and What We Must Aim For.

Human immunodeficiency virus type 1 (HIV-1) is the major cause of acquired immunodeficiency syndrome (AIDS) in humans, where the immune system totally succumbs to the virus. A large proportion of the AIDS infected belong to developing countries and AIDS prevalence is intensified by severe poverty, malnutrition, and famine; fatal illnesses with a scorn shortage of medical amenities complemented with the lack of education and development. Current Pakistani health system setting is in a dire need of improvement. Low literacy rates, high birth rates, and associated maternal mortality plus a lack of clean drinking water and appropriate sanitation system have a serious impact on general living conditions contributing to a relatively short lifespan. HIV is, therefore, becoming a growing health concern in Pakistan with a rapid rise in the reported cases. AIDS is most prevalent among injection drug users (IDUs), male/female sex workers, and unchecked deported migrant workforce. To combat this virus, the Pakistan Government has been working hard over the past few years with local bodies and international organizations in an effort to combat this menace. This review aims to discuss the risk factors for the rise of this epidemic in the country and the recommendations, efforts to be done to address this alarming issue.