Only 10% of babies with Edward syndrome survive beyond 5 years. This is a genetic disease arising due to
Only 10% of babies with Edward syndrome survive beyond 5 years. This is a genetic disease arising due to
Select an option to attempt
Correct Answer: Option B
Explanation
Edward syndrome (Trisomy 18): caused by the presence of THREE copies of chromosome 18 (Trisomy 18) instead of the normal two. Aetiology: non-disjunction during maternal meiosis (usually meiosis II) resulting in an egg with two copies of chromosome 18; most cases (~94%) are full trisomy; ~5% mosaic; ~1% translocations. Clinical features: severe intellectual disability, heart defects (VSD, ASD), micrognathia, rocker-bottom feet, overlapping fingers, omphalocele, growth restriction. Prognosis: ~50% mortality within first week; only ~10% survive beyond 5 years (as stated). More common in advanced maternal age (AMA). Incidence: ~1/3000–5000 live births. Second most common viable autosomal trisomy after Down syndrome (Trisomy 21). Trisomy 13 = Patau syndrome.