Dysplasia Boomerang (Boomerang dysplasia) - Gen FLNB.

The Boomerang dysplasia is a disease that affects the development of bones throughout the body. Affected individuals are born with clubfoot and dislocations of the hip, knees and elbows. In addition, the bones of the spine, ribs, pelvis and extremities may be underdeveloped or, in some cases, absent. As a result of abnormalities in the bones of the extremities, affected individuals have arms and very short legs. The steep slope of the femurs gives way to "boomerang".

Other signs and symptoms of the disease may include encephalocele, omphalocele, a big nose with very small nostrils and an underdeveloped septum, and an underdeveloped ribcage that affects the development and functioning of the lungs. As a result, those affected are often born dead or die shortly after birth due to respiratory failure.

This process is due to mutations in the gene FLNB, located on the short arm of chromosome 3 (3p14.3). This gene encodes the protein filamin B. This protein helps constitute the cytoskeleton which gives structure to the cells and allows them to change shape and move. Filamin B is especially important in skeletal development before birth. This protein is expressed in chondrocytes. Furthermore, the protein appears to be important for normal cell growth and proliferation, differentiation of chondrocytes and cartilage ossification.

They have identified at least 2 mutations in the gene FLNB in people with Boomerang dysplasia. These mutations change individual amino acids in the protein filamin B or remove a small part of the protein sequence, which leads to an abnormal protein. This abnormal protein appears to have a new atypical function that interferes with normal proliferation or differentiation of chondrocytes, deteriorating ossification and leading to the signs and symptoms of Boomerang dysplasia.

This disease is inherited as an autosomal dominant, which means that a copy of the altered gene in each cell is sufficient for alteration is expressed. Almost all cases are due to new mutations in the gene and occur in people with no history of disease in your family.

Tests in IVAMI: in IVAMI perform mutation detection Boomerang dysplasia associated with, using the complete PCR amplification of exons FLNB 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).