DiGeorge Syndrome

For DiGeorge's Syndrome, remember CATCH22!

C - Cardiac defects
A - Abnormal facies
T - Thymic hypoplasia
C - Cleft palate
H - Hypocalcemia
22 - Chromosome 22 mutation

Now why would a mutation on chromosome 22 lead to thymic hypoplasia? Well chromosome 22 is responsible for the development of the thymus from the third and fourth pharyngeal pouches. No thymus, no T-cell formation. No T cells, immunodeficiency.

Thanks to my friends: Tomasz, Danny, and Joy!