Glomuvenous malformations (MIM 138000) are rare vascular malformations consisting of glomus cells, and in affected individuals, lesions may appear in any number anywhere on the body. We analysed the DNA of one family with hereditary glomuvenous malformations and identified the mutation causing the disease in the glomulin gene on chromosome 1 p22. The deletion started at base pair 157: 157delAAGAA, which is a deletion of five base pairs. This mutation has been found in Europe, the USA and Australia, suggesting a founder effect with common ancestry. Thus far, no second-hit mutation for the 157delAAGAA mutation has been identified.