The skin punch biopsy has been around for decades, having been traditionally used by dermatologists to evaluate suspicious skin lesions. More recently, neurologists have been recognizing its value as a diagnostic tool in patients with suspected small fiber neuropathy. In addition, researchers over the past several years have been working on a reliable assay to evaluate skin samples for α-synuclein deposition. The use of skin biopsy to evaluate phosphorylated α-synuclein (p-syn) has been demonstrated in patients with synucleinopathies such as Parkinson disease (PD) and pure autonomic failure [
1] and, more recently, idiopathic REM sleep behavior disorder [
2]. …