Holt Aram syndrome is caused by mutation of:: (A) TBX5, (B) NKX2.5, (C) Lefty, (D) None of the above
Answer is A. Mutations in the TBX5 gene result in Holt-Oram syndrome, characterized by preaxial (radial) limb abnormalities and atrial septal defects.Ref: LANGMAN'S EMBRYOLOGY 11TH ED Chapter 12.