DICER1 syndrome ... (DICER1 syndrome) - Gen DICER1            

DICER1 syndrome is a hereditary process that increases the risk of a variety of cancers and noncancerous, more often certain types of tumors that occur in the lungs, kidneys, ovaries and thyroid gland. Affected individuals may develop one or more types of tumors, and members of the same family may have different types. However, the risk of tumor formation in individuals with DICER1 syndrome increases only moderately compared to tumor risk in the general population; most individuals with genetic changes associated with this condition never develop tumors.

People with DICER1 syndrome who develop tumors develop more often pleuropulmonary blastoma. These tumors occur in infants and young children and are rare in adults. Pleuropulmonary blastoma is classified into three types depending on tumor characteristics: in type I, the growths are composed of cysts; in type II, they are containing both growths cysts as nodules; and type III, growth is a solid tumor that can cover a large part of the thorax. Pleuropulmonary blastoma is considered cancerous, and types II and III can metastasize, often in the brain, liver or bones. Individuals with pleuropulmonary blastoma may also develop a pneumothorax that can lead to the collapse of a lung.

Cystic nephroma, which involves the development of multiple benign cysts in the kidneys, can also occur in people with DICER1 syndrome usually develops in early childhood. DICER1 syndrome is also associated with the development of ovarian tumors known as Sertoli cell tumors-Leydig, which usually develop in affected women in their teens or twenties. Some cell tumors Sertoli-Leydig free testosterone; in these cases, affected women can develop facial hair, deep voice and other male characteristics. Some women have irregular menstrual cycles affected. Cell tumors , Sertoli-Leydig usually not cause metastasis. People with DICER1 syndrome are also at risk of developing a Multinodular Goiter thyroid caused by the growth of nodules. Nodules are generally slow growing and benign. Despite this growth, thyroid function rarely be affected. Rarely, people with DICER1 syndrome develop thyroid carcinoma.

DICER1 syndrome is due to mutations in the gene DICER1 (dicer 1 ribonuclease III), located on the long arm of chromosome 14 (14q32.13). This gene encodes a protein that plays a role in regulating the activity of other genes. The Dicer protein is involved in the production of miRNA, for which cleaves RNA molecules. MicroRNA control gene expression by blocking the protein coding. Through this function in the regulation of gene expression, the protein Dicer is involved in many processes including growth, proliferation and cell differentiation.

Mutations in the gene result DICER1 encoding an abnormally short Dicer protein is probably unable to produce microRNA. Without regulation microRNA genes are expressed abnormally, which could cause the cells to grow and divide uncontrollably leading to tumor formation.

DICER1 syndrome is inherited as an autosomal dominant, which means that a copy of the altered gene in each cell is sufficient to express syndrome. It is important to note that people inherit an increased risk of tumor development; many people who have mutations in the gene DICER1 do not develop abnormal growths.

Tests in IVAMI: in IVAMI perform detection of mutations associated with syndrome DICER1, by complete PCR amplification of exons DICER1 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).