Increase acetylcholinestrase in amniotic fluid indicates -

Ans. is 'a' i.e., Open Neural Tube Defect Prenatal diagnosis of neural tube defect In intra embryonic life, neural tube is open at both end and freely communicate with amniotic cavity. Failure of closure of neural tube results in persistant of this communication. o This allows excretion of following fetal substances into amniotic cavity ? 1) Alpha - fetoprotein 2) Acetykholinesterase o These serve as biochemical marmkers for NTDs for prenatal diagnosis.