Coq8b, also previously termed ADCK4, is a gene involved in the biosynthesis of coenzyme Q10 (CoQ10) [1-9]. CoQ10 is a key component of oxidative phosphorylation in the mitochondria, playing a vital role in energy production and maintaining mitochondrial function [1,4].

Mutations in Coq8b are mainly associated with steroid-resistant nephrotic syndrome (SRNS) and glomerulopathies. In Chinese children, it is one of the common causes of adolescent-onset proteinuria and/or chronic kidney disease (CKD) of unknown etiology [2]. Patients with Coq8b mutations often present with proteinuria and/or advanced CKD at diagnosis, and renal biopsy usually shows focal segmental glomerulosclerosis [2]. Early detection of Coq8b nephropathy, followed by CoQ10 supplementation combined with an angiotensin-converting enzyme (ACE) inhibitor, could slow the progression of renal dysfunction [2]. Kidney transplantation in patients with Coq8b-related end-stage renal disease (ESRD) has a low recurrence risk of proteinuria, but graft rejection should be monitored [3]. Additionally, bi-allelic variants in Coq8b may also lead to non-syndromic retinitis pigmentosa, possibly by impairing CoQ10 biosynthesis [4], and a common polymorphism in Coq8b may act as a modifier of thoracic aortic aneurysm severity [5].

In conclusion, Coq8b is essential for CoQ10 biosynthesis and mitochondrial function. Research on Coq8b-related mutations has significant implications for understanding and managing diseases such as SRNS-related glomerulopathies, non-syndromic retinitis pigmentosa, and thoracic aortic aneurysm [1-9].