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GTR Home > Conditions/Phenotypes > Hypertrophic osteoarthropathy, primary, autosomal dominant


Autosomal dominant primary hypertrophic osteoarthropathy (PHOAD) is characterized by 3 major features: digital clubbing, periostosis, and pachydermia. Patients may also experience joint swelling and pain, and some have reported gastrointestinal symptoms, including watery diarrhea. Males are more commonly affected, and more severely affected, than females (Lee et al., 2016; Xu et al., 2021). Touraine et al. (1935) recognized pachydermoperiostosis (PDP) as a familial disorder with 3 presentations or forms: a complete form with periostosis and pachydermia, an incomplete form without pachydermia, and a forme fruste with pachydermia and minimal skeletal changes. Genetic Heterogeneity Autosomal recessive forms of PHO have been reported (see 259100), including PHOAR2E (614441), which is also caused by mutation in the SLCO2A1 gene. [from OMIM]

Available tests

3 tests are in the database for this condition.

Genes See tests for all associated and related genes

  • Also known as: MATR1, OATP2A1, PGT, PHOAD, PHOAR2, SLC21A2, SLCO2A1
    Summary: solute carrier organic anion transporter family member 2A1

Clinical features


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