December 22, 2010 — Connective Tissue Gene Tests (CTGT) continues to increase its repertoire of diagnostic tests, today announcing that it has added new tests for Desbuquois dysplasia (DBQD; MIM 251450) and Torg-Winchester syndrome (MIM 259600).
DBQD is an autosomal recessive chondrodysplasia characterized by severe prenatal and postnatal growth retardation, rhizomelic dwarfism, joint laxity, thoracic hypoplasia and progressive scoliosis. It has recently been divided into three distinctive subtypes. Detailed clinical information regarding this disorder can be found on the Desbuquois dysplasia page on CTGT's web site.
Mutations in the calcium-activated-nucleotidase 1 (CANT1) gene have been described in type1, type 2, and the Kim variant of Desbuquois dysplasia. CANT1 analysis has failed to identify mutations in some patients reported to have type 2 Desbuquois dysplasia.
Torg-Winchester syndrome is an autosomal recessive disorder. It was originally defined as three separate entities: Torg syndrome, Winchester syndrome and multicentric osteolysis with nodulosis and arthropathy (NOA syndrome). The 2006 revision of the Nosology of Constitutional Disorders of Bone classified Torg and Winchester syndromes as a single entity with NOA syndrome as a variant. Detailed clinical information regarding this disorder can be found on the Torg-Winchester syndrome page on CTGT's web site.
Torg-Winchester syndrome and NOA syndrome are caused by loss of function mutations in the matrix metalloproteinase 2 gene (MMP2). This gene encodes type IV collagenase also known as gelatinase A.
The new tests may be ordered using the requisition forms on CTGT's web site. As new tests are added frequently, CTGT advise clients to regularly download the latest requisition forms from the Requisition Form page on the web site.