The second region with evidence of parent-of-origin biased methylation in peripheral blood at a Mendelian disease gene overlapped the last intron of the WW-domain-containing oxidoreductase, WWOX, on 16q23.1, a gene associated with epileptic encephalopathy (MIM #616211), esophageal squamous cell carcinoma (MIM #133239), and spinocerebellar ataxia (MIM #614322) inherited in the autosomal recessive manner. Here, WWOX is linked to esophageal squamous cell carcinoma.