DiGeorge syndrome is associated with deletion on which chromosome?

DiGeorge syndrome is associated with deletion on which chromosome?

• A. Chromosome 21
• B. Chromosome 22
• C. Chromosome 11
• D. Chromosome 18

Answer: (B)

DiGeorge syndrome results from a microdeletion in the 22q11.2 region on chromosome 22. This loss of genetic material disrupts development of neural crest–derived tissues, causing thymic and parathyroid defects and common heart outflow problems, which explain the characteristic features of the condition. Because the syndrome is defined by a deletion on chromosome 22, chromosome 22 is the correct choice. The other options point to different conditions—chromosome 21 is Down syndrome, while deletions on chromosomes 11 or 18 are associated with other syndromes and do not cause DiGeorge.

DiGeorge syndrome results from a microdeletion in the 22q11.2 region on chromosome 22. This loss of genetic material disrupts development of neural crest–derived tissues, causing thymic and parathyroid defects and common heart outflow problems, which explain the characteristic features of the condition. Because the syndrome is defined by a deletion on chromosome 22, chromosome 22 is the correct choice. The other options point to different conditions—chromosome 21 is Down syndrome, while deletions on chromosomes 11 or 18 are associated with other syndromes and do not cause DiGeorge.