However, among these disorders, BRRS is considered to be allelic only to CS, as both syndromes have been associated with germline mutations in the tumor suppressor gene phosphatase and tensin homolog (PTEN [MIM 158350]) at 10q23.3, the latter excluded as a candidate locus for the other overlapping syndromes.6–9. This evidence concerns the gene PTEN and Bannayan-Riley-Ruvalcaba syndrome.