<prompt> Most specific marker for neural tube defects isAlpha-fetoproteinUnconjugated estriolAcetylcholinesterasePseudocholinesterase  <response>: Both alpha-fetoprotein and acetylcholinesterase in amniotic fluid are markers for neural tube defects. But acetylcholinesterase is the most specific marker. Ref : Dutta book of obstetrics 8th Ed 