Instituto Valenciano de Microbiología
(IVAMI)

Masía El Romeral
Ctra. de Bétera a San Antonio Km. 0.3
46117 Bétera (Valencia)
Phone. 96 169 17 02
Fax 96 169 16 37
Email: 
www.ivami.com
CIF B-96337217

Print

Bannayan-Riley-Ruvalcaba syndrome ... (Bannayan-Riley-Ruvalcaba Syndrome) - Gene PTEN

The Bannayan-Riley syndrome-Ruvalcava (BRRS) belongs to a group of diseases with variable but overlapping phenotypic manifestations including hamartoma syndromes called tumor (PTEN or PHTS). These conditions include mainly Bannayan-Riley-Ruvalcava (BRRS) syndrome, Cowden syndrome (CS) and the Lhermitte-Duclos disease, which is considered a phenotypic variant of Cowden syndrome.

The Bannayan-Riley syndrome is characterized by Ruvalcaba-macrocephaly, multiple cancerous tumors and hamartomas, and the presence of dark freckles on the penis in men. Signs and symptoms of Bannayan-Riley-Ruvalcaba syndrome are present at birth or manifest in early childhood. At least half of affected infants have macrocephaly, and many of them also macrosomia. About half of all children with Bannayan-Riley-Ruvalcaba syndrome have mental retardation or developmental delay, particularly the development of speech and motor skills, which can improve with age. About half of all people with Bannayan-Riley-Ruvalcaba syndrome develop hamartomas (hamartoma polyps) in their intestines. Often, other noncancerous the Bannayan-Riley-Ruvalcaba syndrome and include lipomas and angiolipomas growths that develop under the skin are associated. Some affected individuals also develop hemangiomas. People with Bannayan-Riley-Ruvalcaba syndrome may also have an increased risk of developing certain cancers. Other signs and symptoms described in people with Bannayan-Riley-Ruvalcaba syndrome include hypotonia and other muscle abnormalities, skeletal abnormalities (hyperextensibility, scoliosis, pectus excavatum), thyroid problems , and seizures.

Characteristics Bannayan-Riley-Ruvalcaba syndrome overlap with another disease called Cowden syndrome. Both processes can be due to mutations in the PTEN gene. Some people with Bannayan-Riley-Ruvalcaba syndrome have had relatives diagnosed with Cowden syndrome and other individuals have the characteristics of both diseases. Based on these similarities, it is proposed that Cowden syndrome and Bannayan-Riley syndrome Ruvalcaba included in the group hamartoma tumor syndromes (PTEN) instead of two superposed considered different pathologies.

In about 60% of all cases of Bannayan-Riley-Ruvalcaba syndrome they have identified mutations in the PTEN gene, located on the long arm of chromosome 10 (10q23.3). The protein encoded from PTEN is a tumor suppressor. They described more than 30 mutations in this gene in individuals with Bannayan-Riley syndrome Ruvalcaba. Some of these mutations change basepairs in PTEN or inserted or deleted a small number of base pairs. Other mutations result in an abnormally short or reduce the amount of enzyme which is encoded enzyme. Approximately 10% of cases of Bannayan-Riley-Ruvalcaba syndrome are due a large deletion of genetic material that includes all or part of this gene. All these genetic changes prevent the enzyme PTEN regulate cell proliferation effectively, which can lead to uncontrolled cell growth and formation of hamartomas and other tumor types. However, it is unclear how mutations of PTEN causing macrocephaly, developmental delay and other features Bannayan-Riley-Ruvalcaba syndrome. When Bannayan-Riley syndrome Ruvalcaba is not due to mutations or deletions of PTEN, the cause of the disease is unknown.

This disease is inherited as an autosomal dominant, which means that a copy of the altered gene in each cell is sufficient for the disease to be expressed.

Tests in IVAMI: in IVAMI perform detection of mutations associated Bannayan-Riley consíndrome-Ruvalcava (BRRS), by complete PCR amplification of the exons of the PTEN gene, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).