(2017), provide evidence of potential adaptation in loci putatively associated with thickened skin, with positive selection in subterranean lineages detected in the loci COL14A1 and COL5A2, which have been linked to the skin diseases punctate palmoplantar keratoderma type I and classical Ehlers–Danlos syndrome. The gene discussed is COL14A1; the disease is punctate palmoplantar keratoderma type 1.