Click here for the AHL content.

Learn.Genetics at Utah is an excellent resource for this topic, and all animations are easy enough to save.

………o0O0o………..

Meiosis:

• Good animation from Biostudio (the one used in the diagrams in the presentation)
• Good animation from Learn.Genetics

Non-disjunction:

• Trisomy from Learn.Genetics (their page on Down Syndrome is here)
• Excellent animation of meisosis I and meiosis II from BioStudio

Karyotyping:

• Animation and have-a-go from Learn.Genetics

Amniocentesis:

• Simple animation from MedIndia
• Video from GoogleVideo

Here’s a patient having an amnio:

Chorionic Villus Sampling:

• Video clip from Discovery Human Body Atlas

Sex and Gender:

• Wellcome Trust Big Picture magazine on Sex & Gender
• Gender testing in athletics ‘imperfect’ (CNN)

……….o0O0o……….

Avoiding invasive tests for Down syndrome:

This news article outlines a new blood test for Down syndrome which does not require the invasive techniques of chorionic villus sampling or amniocentesis. See if you can work through the statistics posted there:

1. What proportion of all pregnancies end up terminating due to invasive tests as a result of a ‘false-positive’ scan result?

2. Compare the proportion of women needing amniocentesis or CVS in cases where the blood test is and is not used.

3. How does the blood test work – what is being detected and how? Find out more.

………o0O0o……….

This is an amazing development, and connects all aspects of the Genetics units: