Kids Only | Gene Games

CHROMOSOME HUNT

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This game is a little harder than the others, but it is good fun. You will need to read about karyotypes below before starting.

If scientists want to see if a person has all the right chromosomes, they do a karyotype. A karyotype is an image of all the chromosomes, matched into pairs and lined up from biggest to smallest, so you can make sure they are all there, and there are no extras.

Chromosomes are easiest to see when a cell is dividing into two. Scientists take a picture of a person's cells when they are dividing. They can see chromosomes quite clearly, but they are scattered all over the place. This picture is called a 'metaphase spread'.

To make a karyotype they have to first work out which chromosome is which. To do this they use special 'paints' or stains to colour the chromosomes. Different chromosomes will have different colours or banding patterns. The scientists can sort the chromosomes into a karyotype. They used to do it with paper and scissors, but now they would use a computer.

Here is a picture of a karyotype where chromosomes have been stained with just one colour.

Remember, humans have 23 pairs of chromosomes, including one pair of sex chromosomes.

Girls have two X sex chromosomes. Boys have one X and one Y sex chromosome.

Would you like to try making a karyotype?

To play the game:

Click on the picture of the metaphase spread at the right of the screen. One of each pair of chromosomes will move to above its number. (These chromosomes are multi coloured because they have been stained using a special technique called "FISH", that uses fluorescent paints of many colours. This makes it easier to tell which is which.)

Next, click on each of the remaining chromosomes and drag it in position next to its partner. The chromosomes will only stay in place if you have put them in the correct places.

There are three karotypes for you to try; a normal male (how do you know it is a male?), a person with Klinefelter's syndrome, and (What is different about their karyotype) a person with trisomy 18 (Edward Syndrome). (What does trisomy 18 mean? Is this person a boy or a girl?)