SCP2 and Leukoencephalopathy: The indispensable role of SCPx in peroxisomal β-oxidation was further exemplified when a homozygous 1-nucleotide insertion in SCP2 in a patient resulted in the complete absence of SCPx protein and led to leukoencephalopathy with dystonia and motor neuropathy, hyposmia, azoospermia, and an accumulation of branched-chain fatty acids [123].