Mosaic 22q11.2 deletion and tetralogy of Fallot with absent pulmonary valve: an unreported association.

Chromosome 22q11.2 microdeletion is the most common microdeletion syndrome. Mosaic 22q11.2 deletions are very rare and only a few have been reported. We describe a case of a neonate with tetralogy of Fallot with absent pulmonary valve with mosaic 22q11.2 deletion. Fluorescent in situ hybridization analysis of lymphocytes showed a hemizygous 22q11.2 microdeletion in 66% of interphase nuclei. Microarray testing confirmed a 1.66 Mb deletion at 22q11.2. The child did not have any clinical manifestations of 22q11.2 deletion other than the cardiac malformation.