DiGeorge subtypes of nonsyndromic conotruncal defects: evidence against a major role of TBX1 gene.
The role of the 22q11 region genes, and among them TBX1, in nonsyndromic conotruncal defects (CTDs) is still unclear. Mice hemizygous at the Tbx1 locus show a remarkable incidence of heart outflow tract anomalies, of the same type commonly found in DiGeorge/Velo-cardio-facial syndrome (DGS/VCFS). Mutation analysis of the TBX1 gene in isolated, nonsyndromic CTDs has not demonstrated any functional pathogenetic variation so far. We screened the TBX1 gene in 41 patients affected by nonsyndromic CTDs of the DGS/VCFS subtype, principally "atypical" tetralogy of Fallot. Besides a few polymorphisms, we did not find any pathogenetic variation. These results do not support a major role of the TBX1 gene as responsible for human nonsyndromic CTDs.
Conti
Emanuela
E
CSS Hospital, IRCCS, San Giovanni Rotondo, Italy. e.conti@css-mendel.it
Grifone
Nicoletta
N
Sarkozy
Anna
A
Tandoi
Caterina
C
Marino
Bruno
B
Digilio
Maria Cristina
MC
Mingarelli
Rita
R
Pizzuti
Antonio
A
Dallapiccola
Bruno
B
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics*; D014644:Genetic Variation; D006330:Heart Defects, Congenital / Q000235:genetics*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007558:Italy; D017422:Sequence Analysis, DNA; D020825:T-Box Domain Proteins / Q000235:genetics*
D020825:T-Box Domain Proteins; C108625:TBX1 protein, human