Chapter 21, Problem 21.8CTA

Summary Introduction

To determine: Whether diagnostic tests give full information on the extent of effects of Down syndrome in an individual child at the time of birth.

Concept introduction: A genetic disorder caused by trisomy of chromosome 21 is called Down syndrome. This results due to a random cell division error, which is known as nondisjunction. The errors occur mostly during the formation of gametes and the majority comes from the mother in the egg. There are various prenatal screening and diagnostic tests to identify Down syndrome.