Identification, Characterization, and Precise Mapping of a Human Gene Encoding a Novel Membrane-Spanning Protein from the 22q11 Region Deleted in Velo–Cardio–Facial Syndrome

Velo–cardio–facial syndrome (VCFS) and DiGeorge syndrome (DGS) are characterized by a wide spectrum of phenotypes including cleft palate, conotruncal heart defects, and facial dysmorphology. Hemizygosity for a portion of chromosome 22q11 has been detected in 80– 85% of VCFS/DGS patients. Using a cDNA selection protocol, we have identified a new gene, TMVCF (transmembrane protein deleted in VCFS), which maps to the deleted interval. The genomic locus is positioned between polymorphic markers D22S944 and D22S941. TMVCF encodes a small protein of 219 amino acids that is predicted to contain two membrane-spanning domains. TMVCF is expressed abundantly in human adult lung, heart, and skeletal muscle, and transcripts can be detected at least as early as Day 9 of mouse development.