Which syndrome is characterized by a combination of multiple anomalies, including the truncus arteriosus?

The syndrome characterized by a combination of multiple anomalies, including the presence of truncus arteriosus, is 22q11.2 deletion syndrome, commonly known as DiGeorge syndrome or velocardiofacial syndrome. This genetic disorder is caused by a deletion of a small segment of chromosome 22 and results in a diverse range of congenital anomalies.

Individuals with 22q deletion syndrome often present with cardiovascular defects, one of the most common being truncus arteriosus. This condition occurs when the embryonic blood vessels fail to separate properly, leading to a single vessel leaving the heart instead of the normal two (aorta and pulmonary artery). In addition to congenital heart disease, the syndrome can manifest with other anomalies, such as cleft palate, learning difficulties, and immune deficiencies, thus presenting as a complex syndrome with multiple affected systems.

In contrast, the other syndromes listed do not typically present with truncus arteriosus. Meckel-Gruber syndrome primarily involves renal cysts and central nervous system anomalies, while Fanconi anemia is associated with bone marrow failure and increased cancer risk, and TAR syndrome (Thrombocytopenia-Absence of Radius) is characterized by the absence of the radius bone in the forearm and thrombocyt