This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
Misexpression of which of the following homeobox genes alters the position of the forelimbs during development: 
Select and explain. 
A. HOXA7, B. HOXB8, C. HOXC9, D. FIOXD10
B: HOXB8
Answer: B: HOXB8 
Explanation: B i.e. HOX B8 Positioning of limb along the cranio-caudal axis in the flank region of embryo is regulated by the HOX (homeobox) genes. Cranial limit of expression of HOX B8 is at the cranial border of the forelimb, and misexpression of this gene alters the position of forelimbsQ.