Such nucleotide alterations in T-box affect interactions with the major and minor groove of the target DNA and produce very important heart defects in the developmental pathways of cardiac morphogenesis.12,13 In this case/control study, to evaluate the somatic TBX5 mutations in hotspot exons, we have screened 95 sporadic Iranian pediatric patients with CHD phenotypes and compared to 82 healthy matched controls using PCR-SSCP and DNA sequencing approaches. Here, TBX5 is linked to coronary artery disorder.