POLG and recessive mitochondrial ataxia syndrome: Conditions such as neuropathy, ataxia, and retinitis pigmentosa (NARP) [36] and Kearns–Sayre syndrome (KSS) [37] arise from mitochondrial DNA deletions, while others, like mitochondrial recessive ataxia syndrome (MIRAS), are due to nuclear mutations in POLG that disrupt mitochondrial function [38].