Velocardiofacial+Syndrome

FALL 2012
mci69@wildcats.unh.edu

====Velocardiofacial syndrome, also known as DiGeorge syndrome, Sedlačlová syndrome, conotruncal anomalies face syndrome, Cayler syndrome, 22q11 deletion syndrome and CATCH 22 [7]. It is a genetic disorder affecting the pharyngeal and neurobehavioral development of an individual, which may result to the following health issues:====


 * conotruncal congenital heart defects (CHD)
 * velopharygeal insufficiency
 * hypoparathyroidism
 * thymic aplasia or hypoplasia
 * craniofacial dysmorphism
 * learning disabilities
 * psychiatric disorders [2].

In some cases, individuals may have more obvious physical and mental features such as the following defects:
 * microcephaly
 * mental retardation
 * short stature
 * slender hands and digits
 * minor auricular anomalies
 * inguinal hernia [5].

There are many variations of phenotypes to every individuals. Some individuals may have a severe symptoms and others may have a moderate to minor symptoms. The pictures show some of the clinical features of VCFS. The prevalence of the disease ranges from about 1 in every 2000 to 1 in every 7000 live births [7]. Since the syndrome covers a wide range of phenotypic features, clinicians use certain clinical features that are easy to distinguish such as congenital heart disease (which occurs in approximately 70% cases of VCFS), palatal anomalies, chest vessel and ocular anomalies, psychiatric disorders, and language and speech impairment [7]. ====In the 1980s, VCFS was confirmed to be inherited as an autosomal dominant gene [7]. The cause of the syndrome, which is a deletion in chromosome 22q11.2 was found in 1992. To understand the syndrome, a genetic analysis of affected individuals were conducted by researchers. Using mouse model, researchers identified Tbx1 as the gene affected by the deletion [4].====

Research Question: 1. What is the role of Tbx1? 2. Where does the mutation occurs? 3. What causes the mutation to occur? 4. What other species that has similar TBX1 gene with human?